Their entire approach to the Timmy issue was hilariously irrational. In what universe is it preferable to use a human as live bait vs just writing off that well and using one of the other five (didn't Maggie say there were that many?) They're in Georgia, not Arizona. Water can't be that damn precious!
I'd be more leery of shooting Timmy because of the possibility that the gunshot will attract more walkers. They seem to be living in some kind of largely walker-free bubble there on the farm (suspiciously so...) They should do everything possible not to upset that, for instance, waiting for Darryl to get back to the farm and use the crossbow.
Anyway, they better treat Glenn like a prince from now on. What a trooper!