Quote ="Saint94"The word pressure obviously doesnt register with him.'"
I don't think you're far wrong there to be fair.
If you hit a 'pressure kick', the next time you have one your brain would think "The pressure wasn't a problem last time so I should be ok here." Next time it happens you're "Well, I've hit 2 of these so I'm clearly ok at handling pressure." Before you know it you've made a habit of it and thinking about the pressure of the situation doesn't even enter your head. It's all psychological.
A friend of mine is in Afghanistan. He says you'd be amazed at how quickly you become accustom to bullets flying past just a few feet or inches from your head. If it happens often enough, the brain very quickly treats something that you or me might find as high pressure, or extremely terrifying, as 'the norm'.
Sinfield's 'Pressure Kicks' have certainly happened often enough for it to be just another everyday part of his job.
Wonderful thing the brain.