Question about "stalled" beer...

Last week (on the 29th) I started a Blegian Dark Strong. The SG right before pitching was 1.079, a wee higher than my last batch, but nowhere near a record breaker. Oh yeah, WL Belgian Golden Yeast (did not use a slurry). For the first day and a half, everything was golden. Then the yeast fell, and my airlock slowed down considerably so I took a SG reading (1.040). Four days later, same reading so I jump-started it ith WL Super High Gravity (woke these guys up!) yesterday and activity has increased greatly. Still, I don't see that fluffy, luscious head of yeast. I want to wait a couple of days before I take another SG reading. Is this okay? Is this just a case of ugly-looking fermentation, or should I duck and cover? Any info would be cool.

Sounds like you are going to be just fine. When you take the the FG I bet you will be happy with where it is. As a note, anytime you have a beer that big it always helps to use a starter to keep that yeast healthy and from getting knocked out by all that alcohol. Good luck with the beer!

much appreciated

Yeah, you can direct pitch up to 1.06 but over that is pushing it. However, it does sound like you are well on your way, the Krausen is normally formed when the yeast is very active and having dropped 40 points you probably won't see much else even after repitching. The second group of yeast should get you where you want to go, but keep an eye on it. If this happens again you can try to rouse the yeast by gently swirling your fermenter, to see if you can get them going again, or so I have read. Thankfully, never had that problem before even with over 90 points.

+1 to all above

This cake also sounds like a good canidate for a yeast washing experiment.