It’s a rule. It’s one thing you don’t do. There will more than likely always be better prices in the future.
I don’t even pay much attention to the VIX except for this. And it WILL NOT always play out immediately, in fact it may take 10 days, 30 days, or 90 days. But this will keep you out of alot of trouble buying extended intermediate tops.
Look above at all the times in the past 3 years the VIX has fallen below 13 and you would have gotten toasted in stocks. I don’t believe this time will be any different.