Thanks for the help, everyone. I'll let you know how it turns out. I just had s 1.073 OG IPA go to completion with WLP001, no issues. Same 1 L starter, agitation, etc. Not quite as big, but big enough. No barleywines in the near future though.

Thanks for the input, all. Here are some more of the details: The first batch was made using 6.6 lbs Munton's Extra Light Liquid extract from a can. The second was with Briess golden light, fresh from the HBS. It was less than a month old. For oxygenation, I pour into the carboy, and then...

I've had two big beers get stuck at about 60% attenuation...extract brews, OG 1.129 (1.7 gallon batch) pitched 11.5 g sachet S-04 (no rehydration), went like gangbusters until 1.050, then nothing...1.101 OG (1.7 gallon batch), used WLP007 w/1 L starter. Fermented down to 1.034 and stuck...