If you feel some resistance but no pain associated with plucking then it's fine. ..... You want to avoid the instant-white blanching of the skin, that's a sign of over treatment, ( not to be confused with bubbling white froth that comes out follicle from lye production.
Resistance but no pain associated is a good sentence to remember.
And yes, I do know what you're talking about. Sometimes I'd treat, and then my skin turns white in the shape of the needle - a white line. I'd think this is partly due to wrong insertion as well as sometimes I'd stick it back into the follicle and this doesn't occur.
The first time I treated my penile shaft I was so eager to remove the hairs since this was something embarrassing I've had to deal with for much of my adult life - I over treated which left lots of scabbing that when healed and fell off left pink skin underneath. I'm just hoping that this doesn't leave permanent and obvious scars as I read from Michael in the forum that this type of skin doesn't scar as it's the epidermis that scars. So - i've learnt that one should never rush!