Kev although I don't do a lot of feeder fishing for snotties these days I can't remember ever having one of my maggots come adrift on a barbless hook and for the past 15 or 20 years (at least) I have only ever used barbless hooks when using maggots.
I've occasionally had worms come adrift but I've never had it happen with a live maggot so far (famous last words Lol.)
Kev if I am fishing a float and using a few maggots in my groundbait then I would much prefer they were live maggots as I would want my groundbait to start breaking down as soon as it reaches the right level in the water; or if I am legering as soon as it hits bottom, I certainly wouldn't want my groundbait to just be sitting there in a static solid lump Lol.
it would take a lot to convince me that on the waters that I fish dead maggots are going to be any better than fresh and well prepared live maggots unless I were to be targeting shoals of very hungry snotties on a very silty bottomed lake; which is the last thing I would want to be doing
Keith