This won't really help you, but I think it's interesting to note that my platies regard a net, and my hand for that matter, as worthy of their greatest coriosity. They will swim into it and nip around it and stuff. So I never have any problems
I really couldn't tell you why they're like this though. Possible because they were born with me and were never moved around much, so they don't associate a net with getting chased.