Yeah, it does tell us that, I didn't dispute it. I don't think Anderson should have played as many Tests as he has.
If you were comparing two bowlers at the end of their careers, who is better? The one who has a career average of 28 and it was steadily around that his whole career, or the one who averages 30, but averaged 36 for a few years and then 24 for the second half of his career?
Ryan Sidebottom averages about 28, but he played just one Test as a youngster, was picked at his peak, and discarded as soon as it was clear he wasn't hitting such heights again. Or Swann, he's averaging 27-28 IIRC, had he played the few years when Panesar was a regular, there's a fair chance this would be about 30-31. Would he then be a better bowler?
I guess what I'm saying is that a career average can tell us as much about whether a player was picked too early, kept too long etc as it does about how good they actually are/were.
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