Have a look at this link

hello, something very interesting :
prusaprinters.org/original-prusa … hs-update/
…Another improvement was to make the parts which were breaking selectively stronger. Simplest way is to place very thin 0.05 mm slits into the problematic area. This forces every slicing software to fill the area with perimeters and effectively making 100% infill where needed.

jean- michel