I ended up pouring off the majority of the dark layer right before pitching ~80 mL of the bottom yeast layer. That was probably the fastest start to fermentation I've ever had. Pitched at 64F after 90 seconds of the mix stir for aeration and I had active fermentation in 3 hours.
Denny, this went into your Noti Brown Ale recipe (although I had to substitute Fuggles for Willamette due to LHBS not having the latter). This is the first American brown ale I've ever made - looking forward to tasting this one! The mild I made with the first pitch of the WY1450 just got bottled and the hydrometer sample tasted great. I'm calling it a trans-atlantic mild as it has English malts and an American yeast.