If you look at it that way, there are benefits to pitching at HK, supposedly, but if the yeast has fallen there's little to no benefit to pitching that un hopped spent DME.
I'm no expert or scientist, but it seems like brewers sweat whether to use 3oz of chocolate malt or 4oz of special b, 1/4 oz of hops at 10 minutes or 5 minutes... then dump in almost three quarts of spent dme makes no sense to me.