High level in navigating the general field is different to high level needed when facing the top players, it's the latter where I feel Murray faltered in slams (I know he was good in masters so no need to bring his H2H or whatever, I don't care for it).
I mean take a look at Nadal vs Murray on grass for example. Murray is a more accomplished grasscourter but in their 3 Wimbledon meetings he's 1-9 in sets, and they're the same age basically. Of course you can counter that with Murray has a great record against Novak on grass and that's fair, but you still get my general point. I don't like Nadal (or especially his fans) but can I really argue that he doesn't have a higher Wimbledon level than Murray? Why didn't he push Nadal to 5 sets in any of those matches? Why did he go down in straights to a 34 year old Fed in 2015 WImbledon SF?
It's not that Murray lost often to the big 3, it's that most of the time he was routined whereas someone with a bigger, more lethal game wouldn't have been. Murray too often gave away too much control to the opponent, and as I sad had that 2nd serve weakness. He had the talent to play more aggressive IMO, he displayed that in say 2012 Olympics or 2008 USO win over peak Rafa but he never developed his game in that direction enough.
