Is cable factor for conduit improved using round terminal boxes?

Been doing some cable factor calculations for plastic conduit. However these exceed the allowable conduit factor due to length of run and number of bends etc.

Want to avoid using next size of plastic conduit. Are the 2-way round terminal boxes (e.g. SF#12607) with screw lids classed as an ‘outlet’ and thus usable to break a conduit run?

If yes, do the inspection corners and Tee pieces also count as an ‘outlet’, thus breaking the run for calculation purposes?

Been looking through the internet, OSG and other books and just cant find anything.

Cheers,