Thank you all for the good info.
As it happens someone else has also suggested taking a few shots in burst mode to see if that helps so i will be having a go at that. I had a look at the Joe Mcnally video.....several times. Its reassuring to know that he has to work at it too.
You have a good point there Yishaq about the focus confirmation light.....I had pretty much forgotten that it was there.
I think I can safely say I will be pretty busy the next few months trying to improve on this. (if not forever!!)
Thanks.