In reply..

I agree with the "perception" that Hyatt usually offers excellant customer service.. Everyone at the LA Hyatt besides the front desk help was wonderful. But compare them to the CHI Hyatt at McCormick center, they don't even compare!!
It was the way she showed me that she did not care about my unhappiness that bothered me as much as my "bad" stay..

I did write corporate and LA directly.. they did everything I could have expected.. apologized, said they'd meet with everyone responsible for the components of the "bad" stay and offered me two free nights anytime over the next year at the LA property.. but I don't think I will be going back to LA..

FYI- I wasn't trying to belittle the entire chain, but I think that my perception of Hyatt as an elite, top tier hotel group may be unfounded.. Other's in their price range and property selection class are better.. But I will continue to enjoy Hyatt properties, as well as their competitors...