He says getting them off the ground, even an inch or two, makes them look better to birds on the wing.

I can see some sense in what he says but surely it doesn’t apply to bare drilled fields, does it?

PIGEON SHOOTING
Peter Theobald
If you are using full-bodied pigeon decoys, I don’t think there is any need to elevate them on drillings.

However pigeon decoy shells do look much better on a peg, particularly the ones with a spring on the top that allows the decoy to move around a bit.