40 overs does indeed make a bit more of a difference, that wasn't my argument. I don't really like 40-over cricket, especially now we've got the Twenty20 Cup and there's substantial evidence that many players are treating it more like an extended Twenty20 game and less like a one-dayer. Even before Twenty20 it was still not ideal (they played 40 overs between 1969 and 1998), either.
45 overs, on the other hand, is little different on an individual basis. You can say "it's 10 overs less" - well, not really, it's 1 over less for every bowler which is virtually nothing in the context of a 10\9-over spell, and it's 5 overs less batting for a batsman, which again isn't really that much when you're only going from 50 to 45 overs. That's still not to say that 50 overs would probably be preferable - but equally I don't think playing 45 overs does any real harm. Good players will still prosper.
And you're vastly overdoing the beer\lager point, TBH.