I've never had a problem with it, but I'm only two all-grain batches in.
I'm no expert, but I did research ph 5.2 a while back. It seemed the consensus among people that actually tested their Mash ph was 5.2 did not do anything. Most people claimed adding Calcium Carbonate (CaCO3) to raise the alkalinity (ph) or Lactic Acid to lower it was a much better solution. I too need to learn more about water chemistry but I usually just ask the guys at the LHBS what I should add for whatever style of beer I am brewing. I usally don't have to do anything. But I do add gypsum to all my IPAs which really brightens the hops.
ETA: The other thing you can do is boil your mash water before starting your mash. This will lower the alkalinity some......but BR water may be too low anyway...not sure.
This post was edited on 1/14 at 2:57 pm