This assertion was never made. I said that I can know as a top is being made etc. (paraphrasing of course)
Nobody said it was a prerequisite, but it can certainly have some advantages (such as a much smoother equity-curve and easier position-sizing).
Just saw this post and I think that it's a pretty good one. Just curious if you ever start with the long vertical and then add the short vertical as it moves in your favor
I do different spreads based on lots of factors. The key for me is not to keep anything short that's very cheap and anywhere near the money, nor anything long that's worth nearly full value that may turn and run against me.