Yup. The arming distance was secretly added in the big patch a while back. Probably to prevent the easy close combat kills that where possible. Also made the underslung shotgun an alternative. Yup. Drifters+Grenade Launcher at any location where you get a hostile medic group clustered up is a combination for massive group kills as you can get into the perfect position and have time to fire both grenades allowing the splash damage to take out most everyone (and throw in an ordinary grenade for extra measure to kill any struggler). That is really annoying whenever it happens.
