Not at all, that is a fundamental misunderstanding of speeds to fly. Min sink is NOT at stall nor is it necessarily anywhere NEAR it. Yes it is slower than best L/D or approach speeds, but not so slow as to stall.
Simple scenario as example... engine failure at height of say 3000', set best glide speed, just for arguments sake lets say sink rate is 500fpm (nice!) you have 6 Min till touch down, if perchance you hit an energy line or thermal etc on that glide and your sink rate goes to 400fpm (net 100fpm lifting airmass at that airspeed), then select min sink speed you might get 300fpm or BETTER depending on the normal parameters between best L/D and Min sink speeds. That would give you and extra 4min of airtime - 66% more (if you hit it straight away and had good air the whole descent - unlikely). If you just maintain that for 1 minute you have nominally gained 200ft over the same time cf best L/D. Return to best L/D if required. Below say 500' you should most certainly be in 'circuit' mode. Of course it still all relates to what you are trying to achieve; make it too a spot to land; get more time to think about it etc. Then there is wind to think about as well.
Another simple scenario... you have an engine failure, select best glide as you need to MAKE that one and only spot, but you might not get there... then a little better sink rate appears on the vario, select best sink, two fold result you are in the 'better' air longer (as you are slower) and have a better sink rate for a time giving you a greater chance of making it than you had than just sticking with best L/D. Tough return to best L/D when the sink rate gets worse again.
In any case, this knowledge of speeds to fly could gain you just enough to make a real difference in an emergency. Really only applies with some altitude though... then again maybe good for use at any stage.