I am going to assume you just suggested a E collar to zap a dog with eclectic zap to stop barking?????
Here are the scientific reasons it not a good idea.
http://www.sfspca.org/behavior/dog_library/choke.pdf Companion Animal Behaviour Therapy Study Group - Electronic training aids Companion Animal Behaviour Therapy Study Group - Electronic training aids International Positive Dog Training Association
My only thought is if your going to use this you really need to know what you are doing and the potential fall out. You cause cortisol levels to rise in the dog and they live in fer of it happening again and cirtisol is a killer.
That you had better have really good timing, keep emotions out of it and be aware that for them to work right you need to zap them hard and hurt once and use it as a threat for life that it may happen again.
ClickerSolutions Training Treasures -- Retraining Manic Alert Barking
JL