In DC, I saw the first preview, the last show and two in between. At the first preview, I thought Bernadette was the weakest of the leads, found her performance lacking and saw a lot of "Desiree" in her Sally. By the closing performance, she completely sold me.
As ljay and I have mentioned, she was utterly heartbreaking.
I also believe she was sick (or suffering from allergies) early in the run. She made every performance, but wasn't up to par...until later on. Then she was brilliant. (Still not as brilliant as Jan Maxwell, but I so adore Jan that I may be a tad biased.

)
"Be on your guard! Jerks on the loose!"
http://www.roches.com/television/ss83kod.html
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"If any relationship involves a flow chart, get out of it...FAST!"
~ Best12Bars