Breather Box? on 2001 Volvo V70 XC

I had a dealer tell me that my XC70 with 129K miles has "positive crankcase pressure" and probably has a clogged breather box. The car runs fine, there are no codes being activated and no dash warnings. The car does not leak oil. I have read posts on other sites where people had this service done and had additional problems. I put a surgical glove on the oil opening and dip stick opening and I can't discern any positive pressure. should I let the dealer do this repair for an estimate of $700? Anybody?

Asked by for the 2001 Volvo V70 XC
I would get another opinion by a Volvo specialist. My sister's nanny had the breather blocked, it built up crankcase pressure and blew out the camshaft seal requiring the timing belt needed to be changed.
1 more answer , 2 more comments
Problem with the breather system is a common thing on these cars over 100K miles. I'd get a second opinion from a Volvo specialty shop- just like Patrick suggested. The best tool to check the crankcase pressure is a Manometer, not a surgical gloves.
There is also a banjo bolt type of breather connection under the intake manifold, which tends to clog.
Actually we never replace only the breather box on these, we do replace the breather hoses too. Cleaning the ports on the engine block is a very important thing to do.

Zee it done in Trenton seems to run the same....I guess it will prevent some problems later.
You won't see much changes on performance, but when you do this repair in time, it will prevent oil burning -which could damage O2 sensors and cat. converters, about a $1000 cost- oil leaks through seals. This is a turbo engine and lubrication for the turbo extremely important, you don't want the oil run low.
You have made a good decision and it will prevent more trouble and actually save you money.