PCV- Good or bad idea for a performance engine?

Id like answers to these questions:

1./ Does the PCV system foul up the mixtures at high revs in a performance engine? (say 350 HP+) -

1b. - If not, why not?

2./ With a conversion to a puke tank - should both sides rocker covers be ventilated or just one?

3/ If I convert to a puke tank with fitted breather cap - should I still run the oil breathers on both rocker covers as well?

3b. - If not, why not?

Hope some of the experienced engine builders / racers on here can help.....