Doesn't Knopfler play 9s? I know Buchanan did, as does Jim Campilongo a fan of his (whom I saw live a week ago). There must be zillion others. Some country players use very light strings, Redd Volkaert, a house hold tele country player uses at least 11s. You play what you play, it's music, not "mine is bigger than yours".

I've played 9-42/46, 10-46/52 on my strat. Currently 10-46 (but I might go back to 9-46 if my mysterious joint ache persists). I play too hard, I guess because I'm used to playing unplugged a lot... so high action and slightly heavier strings seem to suit my style.
----------------
Ronnie Earl: 'Music is not a sport, there's no competition'