Well, as long as you let people turn it off, it's fine with me, I guess. It just seems like a monumental inconvenience when actually learning proper security precautions is so much easier and will benefit you far more in the long run than having Jagex watch over your shoulder. Really, if you don't run around handing out your password to any yahoo that can ask for it and downloading anything and everything, you have absolutely nothing to fear. Furthermore it certainly would be possible for a sufficiently advanced keylogger or a keylogger written specifically for this purpose to figure out which numbers you're using. All you'd have to do is match up the clicks to a screenshot.