Train what you race, race how you train . . .

TRIumphant

I know that every book, magazine and coach quotes the line "train what you race, race how you train" at you, but I find that the moment the klaxon goes off, or someone shouts go, my swim goes to pieces, and it takes a few minutes to get back into rhthym. Anyone know how can overcome this in training, or utimaely is racing the best training.