Is a valve cover breather bad for the 4.6????

[96_4.6]

I was going to take out the long plastic tube that goes from the valve cover across the engine and into the cold air induction and plug the hole on the cold air induction and put a valve cover breather in the valve cover. Reason being out of nowhere the guy across the street who has lived there for 5 years and I've never talked to him came across the street when I was installing my spacer and havin a small problem and he was telling me how he helped designed the intake and other parts for the 99 cobra and how he was on the svt team and he was showing me pics of him on the track in the 2000 cobra R goin 140 in 4th gear wow. I asked him whats with the tube and he said I could just plug the hole and get a valve cover breather cause that tube gets in my way sometimes when I'm workin on the engine but I was reading in the winsor room that its bad cause its unmetered air, help...thanks