I think it is just whatever you get used to.
After nearly 20 years on SPDs, I gave flats a try for a recent weeks holiday in mid/north Wales.
Initially found them odd but after a couple of rides had no problem with grip or tecnique. Had a couple of offs that would have been potentially nasty in spds as I was caught out by a section and fell to the side essentially down a steep slope. Just jumped off the bike, fell over and rolled a bit. With spuds it would have been different – or would I have commited to the section more and not come to a halt? hmm.
After the week riding I thought I’d made a good decision to change, but have just gone round locally (Cannock) and felt totally uneasy and wrong with the flats…doh
Anybody want to buy a 100 mile old pair of Vaults? haha.