I told you this in the league and I'll repeat it here: this is a hobby for most of us. I don't have the time to micro-manage teams and certainly not teams that are going to be bad. You seem to define tanking as not putting in 100% effort; I don't think that's a reasonable standard. I don't put 100% effort into any of my teams. I can't. I don't have that kind of time. I do the best I can, but players are tired sometimes. It's going to happen.
Nobody likes players with good talent losing on purpose to acquire more good talent; however it's not realistic to expect people to do what you do. If someone is clearly throwing games, that's one thing...but it's very hard to prove. Stuff happens. Real-life gets busy. It's hard enough to find owners in this game sometimes, now you want to limit it to people up to your standards? You may have a tough time playing in any leagues if that's the goal.
Enjoy the game. If you don't enjoy a league, leave the league. I've done it. There's no need to create a thread like this implying that the commish encourages tanking. That's not true and completely misleading.