I appreciate the feedback folks, and I suspect the capped syrup will go on a couple days from now...supposed to be sunny and low 30's, that is the best we will see in the foreseeable future.
But I still want to get at the heart of my question: If the bees are at the top does that provide conclusive (or at least strong) evidence that they are out of stores?
I took some more time and set up a dummy hive in the shop with 2-8 frame deeps of capped syrup (from deadouts) with hive stand placing about the same as on the hive in question. Then did the heft feel thing. It actually didn't feel all that different from the living hive....certainly nothing like empty. Now I do understand that they can have left food below them on the outside which they won't reach in the hard cold, but on days like this relatively active don't they move stores around?
I just feel like I have read a lot about how clusters can sometimes spend all winter on the top. Mostly I hear this from folks who don't like top entrances and argue that is where it is warmest (when it is warm at all). This hive doesn't have a top entrance but a quilt box instead.....
If they have enough stores, am I not doing them a disservice by adding another deeps worth of space....I mean there is a reason they get "crowded down" int he fall?