I've seen several matches on DVD at majors where people are just complete spastic, moronic fools.  I mean, it's embarrassing to watch them - and what kills me is they continue those some antics at subsequent tourneys.  How can they act in that manner and not want to dig a hole for themself to hide in for the next 12 months at least, let alone repeat that same behavior at the next tournament? 
I am talking about PMs here.  Not the garden variety bar player.  
Like I said, picture them naked.  That's all it will take for you to cool down, relax and stop taking it all so seriously - that way, you can get back to concentrating on kicking their ass.