Happened at our table a couple of months back.
Lol never once needed knock. Astarion (and later respecced roguelock Wyll) almost never failed, especially with guidance. And even if you fail, I never once had single digit thieves tools.
SwA is goddamn awesome though, totally agreed. Talking to the Rothes in the underdark blew my mind
There are some doors that are impossible to lockpick throughout the game, unless you use Knock to unlock.
I don’t recall any that could be opened with knock but could either be picked or destroyed. I do remember many that required huge amounts of damage to dent though.
There are a few that have DC 30 and can’t be broken. That’s not impossible, but it’s still hard even with a character built for it.