I remember a few years back when someone was in here touting the 7-10 day rule. I was skeptical of their use of it. I didn't think, after having studied Gann pretty extensively, that they were using it correctly. Many people do that with Gann's stuff.

But the way you have described it as being something to look for at the tail ends of bigger moves is an accurate understanding of Gann's use of the 7-10 day rule. It likely means little inside a tight trading range. Personally, I think it was Gann's way of speaking to blow off moves. Maybe, if one was to study the phenomenon of blow off volume in conjunction with a 7-10 day "blow off" move, it might be beneficial. I don't know that to be a fact as I never quite got the hang of understanding volume as a trading aid.

Here is one statement in the Gann course on 7-10 day rule:
"when an option of grain is very active, declining fast and making lower tops and lower bottoms each day, after it has declined
7 -10 days or more, you should make your stop loss order 1 cent above each day’s top, and when your stops are caught, reverse position and buy
placing stop loss order 1 cent under the previous day's bottom.

When an option is very active and advancing fast, after it has advanced 7-10 days or more without breaking a previous day's bottom, you should
follow your purchase up with a stop loss order 1 cent under each day's low until the stop is caught. Then reverse and go short placing a stop
loss order 1 cent above the previous day’s top.

But do not consider that the main trend has changed up or down until an option crosses a trend line top or breaks under the last trend line bottom."

He also speaks to 7-10 week moves.

*****
I am also familiar with taking a trade off before its time. Cutting ones nodes off to spite their wanger is what I have dubbed that particular technique. One I have have, unfortunately, mastered from time to time. hahaha