Looks like I caught the tail end of this but heres my 2 cents on it.
I would never try to lose on purpose. It is wrong. The whole point of fantasy football is to win each week. But beyond just the ethics of it, it could just as easily bite you in the butt, as the team you "helped" could end up beating you in the playoffs.
I play to win each week, regardless of other circumstances. If your team is good enough, you'll have a good chance of winning the league. I wouldn't mess around with trying to dictate your matchups, or who makes it and who doesn't.
If that happened in my league I would kick the culprit out of the league. I've been in leagues in the past where an owner doesn't change his lineup for like a month, and everyone gets freebies. That is bad enough right there, but to lose intentionally, is just wrong, and is as bad as cheating IMO.