I wonder if it would be easier to put clipless on all or none of the bikes.
Having half and half could be problematic.
Plan ahead... I suppose if you were planning to "track stand" at the top of the hill and not unclip, that could have complicated things a bit.
My worst problem is on my own driveway when I can lose traction. But, I've learned my lesson and will just bail if I lose forward momentum.