I took a vial of WLP002 out, thawed it in my hand and pitched it into ~200ml of starter wort last week. It took 2 days, but that fermented out and the whole lot went into a larger flask with another 500ml. 3 days later I cold crashed and decanted off about 300ml, and then added another 1500ml, which is spinning away nicely right now.
I don't know how the thaw/refreeze/thaw impacted overall cell counts, but I do know that I'm growing yeast and the starter beer does taste normal.
I'll report back after my brew on Wed ferments through (planning a 1.090 English barleywine)