The thing is, you don't have to get it all at once, and you don't have to get it right first time either. If you miss it this time round, you can get it the next time.
And you don't have time to worry about the mistakes you make, and sometimes the turn out to be mistakes worth incorporating.
That's the great thing with this type of music we play. The whole is far greater than the parts. A bunch of people who individually mightn't be that hot - but put them together, and just now and then it's sheer magic.