Yesterday I was randomly looking through the GG when I stumbled upon how to differentiate between formations without having to click on each unit or look at the Headquarters screen. The operation also prevents having to find where replacement leaders are on the Headquarters roster because the original leader died, which is very annoying.
It took me 3 years to figure out, so I'm going to share it with everybody in case there are any people like myself that didn't read the manual

but are active on the forums.
- Just press 5 and you can find out which formation is which and it even tells you the leader so you don't accidentally put him in the front of the banzai charge

(it also is nice for rallying purposes).
K.