I think it might be time to accept that slowing down a bit is what you should be doing all the time.
I'd be happy to slow down a bit if it allowed me to win.
It's nice that you've proved for the 37th time that you navigate better when you slow down. Adding to that, regardless of who else is racing that is faster than you, you will still perform better by slowing down! :-)
The other thing is that if you slow down and run at a pace you can read the map consistently then that pace will start getting faster. If you keep running faster than you can read the map then you will not get any better at reading the map.
I think you should slow down a bit more too!