Back Button Focusing

Just don't get the point really - finally figured out how to do it last night after seeing a number of Fuji owners rave about it.  I find it cumbersome, maybe because of my chunky finger tips and the button is soooo small and I wonder just how many fab pics I've missed by not being able to press the shutter again quickly.  If anyone can enlighten me I'd be grateful.  Only took 2 photos today and this is one of them.  This morning was full on but lovely to stop for an hour or so to have a cup of tea with L and a catch up.  Don't know where the afternoon went, waiting for some folk to arrive and then am looking forward to a lazy evening.

Have a good weekend everyone.