Over the past 2 years though, making ATHs hasn't really been that spectacular.
Who knows, but its obvious that breaking highs hasn't lead to huge rallies for the past 2 years.
True. I actually wrote about that in this journal in June and I'm not saying we will have huge rallies from here - just pointing out the obvious which is that we're making ATHs and currently going up.
Most of the sizeable corrections have had ample opportunity to join on the short side, so better to wait for confirmation than shorting a rising market and being continually stopped out, IMO.