He might have been a different player had he not put his body on the line so often to incur fewer injuries.
I think that was part of it, yes.
Being "injury prone" in a general (and very vague, from a scientific viewpoint) sense is...well, one thing.
Some players may be predisposed to certain types of injuries (which may not be known at the time). Others may be just plain unlucky.
But Robson played in a different era, where putting yourself on the line (as you say) was very much a
thing for a certain kind of player (a leader, a
general on the pitch - which Robson very much was). And - yes - the combination of being a less than super professional
athlete (the man loved his booze - this is well known) AND the tendency to "give it all" on the pitch (one could say that this was something he was
expected to do - and something he actively tried to live up to)...well, not ideal.
Anyway - injury free Robbo playing at roughly his top level all season (in his prime, at that): United win the league under Big Ron at some point (obvious case in point would be the 1985-86 season, where we
won the first ten games: at the end of the season, Robson had only played HALF of all fixtures due to bloody injuries). He was
that good, easily. And - I could add - the team was much better than is sometimes suggested, i.e. the idea that Fergie took over a shite team and turned it into gold. He did not. He took over a deeply
flawed team (not least in terms of professionalism) - but United weren't miles off Liverpool (or Everton) under Big Ron.
EDIT The '84 CWC campaign is very interesting with regard to both how good Robson was - and what level United as such were under Big Ron: United came back from a 0-2 defeat in Spain to beat Barca (featuring Schuster and Maradona) 3-0 at Old Trafford in what many consider Robson's ultimate performance (he utterly dominated the match and scored twice).
We then proceeded to the semi-final, facing a legendary side - Trappatoni's Juventus, featuring Scirea, Gentile, Cabrini, Tardelli, Rossi and Boniek .
Oh - and some bloke called Michel Platini.
United managed a 1-1 draw at Old Trafford - and then lost 1-2 in Turin after a goal by Rossi
in the last minute of the match (typical enough Juve style).
Robson didn't play in either leg, as he was (of course) injured.
We had multiple very good-to-brilliant football players: Albiston, Wilkins, Stapleton, Whiteside, Hughes, Moses (the latter often heavily underrated) and more (who were at the least decent top level domestic players at the time). And that's without mentioning the genius named Paul McGrath, who in my opinion is the best defender who ever played for Manchester United (even when playing with a massive hangover, which he usually did).
Now, add a prime Bryan Robson to one of those legs (preferably both) - and, yeah, there you are. Juventus won the tournament that year. Might have been a different story with Robson in the mix.