Well, I see your point, but to be fair, combat engineers are around for more than just conducting breaches - I recall that they got a good workout digging survivability positions, and between their Bradleys, bulldozer/"farm implement" type vehicles, and their secondary mission of "fight as infantry", I would think that engineers would be a very welcome addition to the severely limited combat power of the Heavy BCT (especially considering the anemic cav squadron that they have), even in the COIN environment. While horizontal and vertical construction may not be a combat engineer's forte, I would think that they would adapt to it more rapidly than any other MOS, and that is certainly useful in COIN. Compare this to the growing MOS of Military Intelligence, which while all agree that it would be nice to have good intelligence on the enemy, more personnel in MI does not equate to more intelligence...

So, we went from one engineer brigade to each heavy division - three battalions, plus one battalion per light/abn/air assault division - along with some extra battalions as corps assets, down to... I think only two mobility enhancement brigades, and a weak engineer company for each BCT...

(Someone with better knowledge of engineering can correct me, of course.)