I think there's a balance that can be found between getting outright aggressive and being too diplomatic. I've told my partners at seminars "We obviously don't agree, so just let me practice my way, ok?" and usually that works. People might be left thinking that I'm stupid for not accepting their wisdom but so far no one has actually started to argue about it.
The thing about people who like to stop your technique in a passive aggressive way seems to be, they don't really like to do it "out in the open" so when I say something about it, they stop.
On the other hand, when people are genuinely trying to help, if I say something, they'll explain what they were after, and then I can either decide to try it their way, or we agree to disagree.