A valid strategy? Absolutely.

Would I use it myself? No, almost never.

You can be 99 % sure someone is going to attack you and then...nothing. I've seen it quite often and have also been there, right up in someones face screaming and shouting, threatening allsorts and then it all sort of just peters out with no actual violence. If I had struck pre-emptively I would have been in twice the number of fights I have.
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