According to RAVE, the "Expansion tank cap relief valve - system operating pressure" should be 1.4 bar or 20 psi.

I recently got my cooling system pressure test done and the mechanic said it "held 14 psi" and he found no leaks. Does this seem correct? Should he had tested it to 20 PSI?

'01 with 57.5K miles...I guess I'm looking for an excuse to do a head gasket job...I figure it is about time. But I'm not loosing coolant and it has never over-heated.

 

If it held pressure it it held pressure. If there was a leak the pressure would have decreased. Front cover leaks can be tricky and evade a pressure tests though. Be happy and flush your coolant at reasonable intervals.

 

Wrong, the system should have been pressure up to around 22 and allowed to hold there for 15 to 20 minutes, if not you just wasted your money.
Are you thinking your leaking coolant?