...In fairness to Gen Hillier, I think the ultimate plan with the .coms was to replace existing HQ's with the .coms. Now if that really was the case, then the issue is completing the transition between the existing structure to the .com structure. Then again, I could be out to lunch on that, but that was the impression I got from the various briefings etc. presented when the plan first came out and the .coms were standing up.
Thucydides, you're as far out to lunch as you think.

Had things gone the way Gen Hillier wanted initially, we would have actually had a fairly streamlined joint strat HQ structure:
3* CFE (Chief Force Employment) with two 2* (Expeditionary and Domestic)
3* CFG (Chief Force Generation) [like US FORSCOM] with the 3 ECS responsive to CFG using a CF managed-readiness model
3* CFD (Chief Force Development) and ECS FD elements under CFD direction.
For those who remember things before, the CFE/Exp/Dom construct would have been near identical to DCDS/COS J3 Intl/COS J3 Cont. That (CFE) was relatively okay, but there was huge pushback on the CFG construct. One environment was particularly vehement in its refusal to accept the CFG proposal, believing that there was essentially no place for large-scale jointness in what it did (both FG and FE). Another environment was relatively okay with things, so long as its responsibilities to existing bilateral capabilities weren't impacted (which it wouldn't have been). The other environment was okay with things generally, particularly the CFG thing, but had some concerns about stewardship/leadership of its generated force abroad, once deployed.
In the end, the pushback was significant enough that Gen Hillier went with the back up plan, COA 2, which was 2 x 3* for CFE functionality (CEEFCOM and CanadaCOM), leaving the FG principally to the environment, then adding some CF-wide enablers (CANOSCOM) to consolidate previously underappreciated/supported logistical issues. CFD survived, but was knocked down from a 3* to a 2*, but at least stewards CF-wide force development as originally intended within Plan A.
The "bloat" as many refer to came principally from the environments not anteing in as much to the new constructs as Gen Hillier had tried to secure (and the environments generally agreed to) - fiefdoms remained and the overall result was that Gen Hillier's vision of consolidated command stewardship was somewhat (significantly?) diluted by functional silos.

Regards
G2G