RE: Is it necessary and what is/are the advantage(s)?
Bob McNally is a big fan of the 'big heads'. I have an article he wrote praising the use...... he mentioned everything from deer to hogs killed very quickly as he wrote...
Anyway - I see no problem - in fact - if you read that article it made ya think - BUT, here is my personal take. As said above less is more in my opinion, and you may ask why ? It takes less to push a 1.125" head and achieve a pass through than it does a BIG head. A pass through with BOTH heads will show the larger creating more blood etc.... but it takes a better placed shot, perhaps a lil luck and a LOT more bow to push the Vortex 2.25" blades (as Bob liked) in a pass through... so personally Id rather shoot a 1 or 1.125" head with less bow, and shoot better in the cold and still get that pass through.... Bob said a lot of good points in the article - it was worth reading.....and opened my eyes some but Id still be a lil worried about those huge blades getting through..... thats a LOT of blade to push.......
I used a Montec G5 last year - a small head but a REALLY nice one. I also used a Steelforce - a real nice head also. BOTH heads passed through and kept going - one into a tree a good bit.... so Ill stick with my well built 1" fixed blades......