"If you do your frame by frame thing and stop as the feet are to together do you really see any difference between a Waltz a Quickstep or a Foxtrot at that point."
Definitely. No one who understands these dances would confuse the passing instant of a passing action with a closing action for a second, as they are fundamental different.
"teaching a Reverse Turn Foxtrot, will have the class freeze as they go from 5 to 6 and then explain that the foot will not stop but will pass into the Feather Finish."
The foot will not stop because the body will not stop. Wheras in waltz the foot will stop because the body travel has momentarily stopped due to converting all the momentum into rise. The waltz action is complete and the foot closure marks the end of the swing - in the foxtrot, you only convert part of your momentum and the closing is quite clearly a passing thing, in no way an endpoint.
That's the fundamental difference you must learn to create in your dancing.
"Once again Rise at the end of step one. Up on two and three. Lower at the end of three. How many of you are taught this, and the differences there are over the same steps in the Waltz."
The major difference at the time when the feet close is not in the textbook foot rise, it is in the completeness of the conversion of momentum to altitude.
The textbook issue is somewhat minor in comparison and somewhat misleading in that the body altitude will experience a continuation upwards as the feet close which is NOT covered in the book (the book does not cover altitude change due to the legs closing and reopening, which has become quite important at today's step sizes)
The contribution of what the book does mention towards the completeness of rise is that the waltz-style commence and continue curves up more sharply, leading towards the complete conversion of momentum. In contrast, the book foxtrot rise is simply from heel lead to moderate toes, along more even path throughout the first step. Thus foxtrot rise (book plus the legs closing altitude gain) merely converts some of our movement and slows us somewhat.