I have always followed pretty much the same split

Day 1: Chest
Day 2: Bi's and Tri's
Day 3: Legs n Abs
Day 4: Shoulders
Day 5: Back

So I hit each muscle one time a week. Now granted I have put on 32lbs since July when I started back, most from muscle memory because I have lifted off and on for 11 years.

However, I have an Amateur Bodybuilder and a few guys who train with him that more or less circuit train or HIT train I guess? They do the whole body every day, just a few exercises for each part, and they rotate the exercises daily, so it's not the same ones everyday. Anyone else do this and have good results?

My concern would be the lack of recovery, altho you're not putting as much stress on the muscle as you would doing 15 sets on it in one day. Just wanted to get some opinions, sort of curious to try this.