Yesterday at night I did an experience, in a common, simple painite hotspot in my home system.
I dropped 150km of the hotspot center, BUT I was very carefully to control perfect the dropping angle and direction, right in the middle of the most intense withe band AND in such an angle to always have in my left the hotspot mark and in my right the planet body.
After the drop, and after I killed a pair of pirates, I only advanced on that withe band, no deviation at any direction. I paid attention to keep my ship always aligned in horizontal plan with the asteroid field width. For 90% of the time, each set of 4 prospectors launched get at least one hit of 41-55 % and one or two of 15-33%, occasionally a pair of 9-12%, but always at least one fat, over 40-42%. I always advanced at the same angle/direction. From 150km to 120 km, the painite concentration maintained stable, in a bit over 1 hour I filled all 320 tones in my Conda, after I was forced to drop some 40-50 limpets in excess to make room for more painite ( I always take the max load in limpets when I go mining, cuz is always better to have more limpets than you need than less...) ;
So, I can conclude, at this day, the search for "overlapping" hotspots it's a bit redundant, when you can get significant amounts from common hotspots, IF you maintain the right path and angle.
Also, seems to me one get better prices IF the quantity is under 512 tones - the price on station presented by INARA is almost the same, if the data is under 15 min. old, if you sell quantities under 500 tones, where the demand is at least double, BUT you get a significant drop in price when you sell over 500 tones at once:
Example - 320 tones - announced price 779k, price 14 minutes old, I sold for 772k;
For 512 tones, the price can go down to 600 even 500k.
Reason why I do not use the Cutter anymore but instead the Conda. Better reward for the time invested.