Have been mulling over the same thoughts myself the last few days WJ.
As well as possibly making a difference in 1962-3, imagine the difference Big Bob Johnson could have made in those really lean years of 1965-68. I recall we were so "light on" in the big man department I recall in one game (if not more) that Tassie Johnson had to do the rucking against the taller top ruckmen from other clubs.
We seemed to lose so many whilst in their prime..even in the good times.. Peter Marquis, Athol Webb? Though maybe they were at the end of their careers..just seems to me they were all playing well when they moved on..Other handy players like Alan Rowarth (injury), Doc Roet, and later David Hone and many more. And losing all 3 of Barassi, Alves and Wells was a tragedy.
Yes Bush Demon..Doc Roet left for overseas after 5 games in 1965 according to Demonwiki. Came back in 1968 for a further 5 games. Sadly missed at that time.
http://www.demonwiki.org/Brian+Roet