If you make a cock up playing ,smile ,nod and find the chord and carry on. If you can acknowledge it your self then folk wont have much of a opinion and none the more for that if you carry on and finish what you are doing then at least you have started and finished.

The only time one should I think stop and start again is in the first few bars.
Its takes time for me to warm up and forget the nerves (6Pints Normally} Then I play a belter and I hear folk say "Stop now Pierre that was great.

Thats the kinda of wit I like .
Does that make sense?
Regards to all Pierre.