Over a year later and I'd also like to state I still have a problem with this. Specifically I noticed the problem recently when I got an 0.8mm nozzle thinking it could make my prints faster. Some overhangs which worked out perfectly with my 0.4mm nozzle are completely ignored when increasing it to the new 0.8mm. The overhangs in question are about 5mm, so we're not talking some tiny little gap, nor is the angle a problem as in one case it is not just an overhang but air printing. Anything further than that aprox. 5mm from the main body and it has no problem generating a support that butts right up against the main body.
Why would the nozzle diameter make such a huge difference? Any ideas how to get cura to generate support as if it were a 0.4mm nozzle, but the rest on a 0.8mm nozzle schedule?
Thanks!