The important thing to keep in mind is that proper washing of performance fabrics will improve rather than damage performance. Proper washing clears the pores to improve breathability, re-lofts insulations and helps DWR coatings to rise back to the surface.
By 'Proper' washing I mean using gentle cleaners that do not strip weather protective coatings, damage hollow-core fabrics or clogg microporous laminate layers - so NOT Tide...or any other comercial laundry detergents. I could say plenty about these products but since we are talking about performance fabrics I'll keep my rant on that topic alone
PH balance is only one componenet of performance fabric wash - the gentle cleaners used break down sweat and body oils that block pores without leaving deposits comercial cleaners leave behind - not to gross you out but your typical commercial cleaners leave so much junk behind that after 10 washings deposits account for nearly 2% of the fabrics weight (see the Clemson University Rinseabilty Test). Many of these specialty performance fabric washes retreat garments with 'wash-in' DWR coatings to help sustain the factory DWR finish to improve longevity.
Don't worry, if you have used commercial detergents or soaps on your garments most quality goods can be restored to their former glory by using a sport specific wash a couple of times to remove the deposits left behind. There are many on the market but I suggest Axis G-Wash