Honestly it is pretty challenging to not leave any trace of the shape of the tip, whether round or otherwise. Some of the best stipple jobs (home done and professionally) you can see faint outlines of the tip used.
I generally will go over it all then if I see some spots that are really obvious, will come back over them with a lighter touch to fade the line out. I have not done it yet, but one could also use the finish tip and the round waffle and have 2 separate patterns to mix it up a bit.
If it is that concerning, I would say your best bet is to use the single point method, and prepare yourself for a long day.