the cue slides because my hand reaches my finish position and stops..
the cue maintains its own momentum because my grip does not actively try to stop it..
I allow the taper of the butt to bring the cue to a stop.
here is a video I posted a while back .. you can kinda see the slide in the first section .. but you get a better look at it in the third section starting at 4:30
http://www.youtube.com/watch?v=igLFXaMUCaQ
my grip does not change at any point during my stroke
wrist is neutral
I don't "time" it.. it just happens... I get clean contact with the CB every time..
some players fight the momentum of the cue and that can cause unpredictable changes in accuracy..