Discussion: Butterfly loops?

So it seems that just about every classic race in Europe these days has one of these things. What is the sentiment about them? Are they de rigeur or a passing fad? Do we need to start using them in the US to be "cool"?

No, the Europeans need to get on board with skipping controls a la the Billygoat. Then they'll be cool like us.

On second thoughts, 'au Billygoat'.

They've already been used in the US -- I've run a couple of UNO courses with butterflies. Personally, I could do without them. Forks, a la quelques Billygoats, would also be cool IMHO.

I think Billygoat can incorporate butterfly loops, even it brings some logistical problems to organizers, and it only fully works with e-punching.

Butterfly loops are used to compensate for a shorter start interval. In a long distance event, the start interval is typically 2 min.when it used to be 3. Buttrflies should split grouped runners. It worked well in WOC 2001 but I'm not sure it has been thorougly analysed since.

The Nordic Open Championships May 25-29 will introduce Micr-o with penalty loops and voluntary controls.....
http://www.noc2005.org/micr-O_description.pdf

My first O meet this past fall, a local UNO meet at College Woods, had 2 butterfly loops. I thought it was a "cool" concept. Seems a person could gain an advantage by recognizing the most efficient routes around these loops rather than by following or grouping up with other competitors. I also thought was an interesting way to get extra controls on to a rather small map. And, lastly, it was interesting having long legs between controls and then coming to one of these loops were legs were a third the distance but still technical. The course had more variety and forced me to stay even more focused.

I also did a Farsta style ski-o course as part of a winter AR wich I didn’t think was that great. I’m not sure how much you can compare Farsta with Butterfly loops – with my limited knowledge I’m assuming that at some level they are both implemented to deter following. However, from the ONE farsta course I did it seemed that other, lucky, teams had pretty distinct advantages with their routes (relative to Control order) just based on terrain, elevation and the trails that connected. This was more of an issue, I think, because of the large distance between controls. I'm not sure if I'm explaining this weel enough, but since we were collecting controls in a different order, at times we were dealing with completly different terrain, elevation, and attack angles, etc. that might have been less ideal. This I think is slightly less the case with Butterfly loops.

I don’t think butterfly loops are a required ingredient for “cool” courses, but I enjoyed them. They would certainly never deter me from doing a course.

I might be misunderstanding you, but the idea with farsta, butterfly loops, and most other forking methods is that at the end, each person (or team in a relay) has run all the same legs in the same direction, but maybe not in the same order. So if that was not the case in your winter race, then the organizers might have messed it up and given some teams an advantage. Also, the control order for each person/team is explicitly marked on individual maps, so there is no freedom to optimize there. (that is to ensure the groups are broken up)

I haven't yet had a chance to race with butterfly loops, although I have had some in training sessions. we probably don't have much need for them in most meets (not enough people), but it is good practice for those preparing for european competition.

I've done butterfly loops twice that I can remember:

* Calero chase Fall 2004.
* Nordic ski-o champs January 2004.

I thought it was a bit boring to visit the same control 3-4 times. Other than that, it's fine by me.

The closest I've come to butterfly loops was Kansas Champs last year, which was a Motala with very short loops. (In a Motala, you run loops in different orders, but there is no variation on each loop). Of course, I've done the Farsta at the Pig many times.

At the Kansas meet, the field was mass started. The Motala format worked reasonably well, although with three loops there are only 6 options, so some people ran together the whole way. The Farsta seems like a much more effiecient way to break up the field.

It seems to me that the disparity of ability levels on most US courses makes such devices superfluous. Perhaps the M-21+ field at a championship event would notice a difference, but I doubt many other results would be affected. I'd rather the organizers put the extra effort into things that improved the meet for everybody.

If I'm remembering correctly there was at least 3 different sets of orders of the controls. However, every team had to do only two loops. Teams did all visit the same controls, but not in the same order and most definatly not the same legs. But it would not at all surprise me if this ski-o course was an americanized, AR'ized version of Farsta.

In the Butterfly loops that I did there was the choice of running the loop in the direction of your choice.

In both experiences there was no control visited more than once.

Sprint/middle at this year PNWOF will have butterfly loops. Major reasons: to dissuade following on open terrain and get most from the most interesting parts of maps.

If teams do not end up doing the exact same sets of legs in the end, it's a farce-ta.

The butterfly loop allows a lot of O in a small area. I set a course last year at Five Ponds, see PG's discussion #23 for June 12, 2004. This was a local meet with the intention of providing skill training. The idea was to set a concentrated course, lots of direction changes, short legs, technical terrain (most controls were subtle reentrants), and as Peter notes, leaf out was mostly done making visibility lower, adding to the challenge. Unfortunately it was a bit more of a challenge for some, but most enjoyed the effort.

Personally I'm not in favor of the things, just adds lots of useless controls and doesn't really split up people that well.

However, (for all the geeks out there), at the recent UK long distance world cup the organisers came up with a nice alternative to the butterfly which makes you visit each control a maximum of 2 times, not 3. Yet it achieves the same effect

see:

http://www.wcup2005.org.uk/page.aspx?id=13997

(you need to scroll down a slight bit)

Did the UK organizers come up with a good Swedish name for this kind of loop?

I've run them, and I've set them. I don't think they are 'ideal' - and I don't know that they would effectively split up groups - but they really do have their place on small areas when it is more interesting to re-visit the same technical control from a new direction than to have an easy leg or a long trail run ... I am talking SMALL areas here!
But as to putting them in to something like the Billygoat? That seems a waste of a good map.

I don't think I would advocate them for anything but training exercises where following is not an issue. I don't see how butterflies would split up groups unless the wings are taken in different order by consecutive runners. It is surprising how different the central control looks upon each return from different directions in a very detailed area. So concentration for training purposes is useful.

Walk wrote: "I don't see how butterflies would split up groups unless the wings are taken in different order by consecutive runners. "

This is exactly how it is done. Runners alternate between left and right wings, thus any runners with adjacent start times will be split at the butterfly.

Problems with this are ...
i) If the runners are of comparable ability, they often come back together at the end of the butterfly.
ii) If the runners are separated by 2, 4, 6, 8 ... start intervals, then they don't get split.

Brian

Any reason a butterfly only has two wings? Not that I'm fan of the extra effort associated with setting up different maps, but having 3 or more loops would do interesting things...

BMay wrote: i) if the runners are of comparable ability, they often come back together at the end of the butterfly.

True, but at least in that case you know that each did his own navigation whilst in the loop and that is the main goal of the butterfly, is it not? To ensure that one runner doesn't hang on to another and gain that advantage...

Couple butterfly loops may help with 2, 4, 6, 8 problem and asymmetrical loops can help with coming to common control at the same time.

Asymmetry won't help with the exit. N>2 loops increases that repeat interval. The coincidence interval can be as high as [N!] (4 loops would give an interval of 24 between repeats) if you use all possible combos. Vlad uses this to good effect in the Pigsta. Coordinating the maps is a pain in the butt though.