E.R. Campbell said:
The force commander is, conventionally, the naval commander, and, as Old Sweat suggested, he has a great deal of responsibility, including the messy business of fighting and winning the "battle on the beach."
In my (albeit limited) experience, the naval commander has nothing to do with the "fighting" on the beach. Her responsibility is to make the final local call on whether to proceed with the landing or not (based on various factors such as was surprise achieved, did the pre-landing bombardment achieve its breaching effect, in view of the relative importance of the mission do the weather conditions preclude proceedings, are support forces in position, etc.). Once the call to go is made and the Army hits the beach, the directing and control the fighting on the "beach" is fully in Army hands. The naval commander's responsibilities are not finished however: For one thing, he must deliver the support expected from the ships involved in the op; for another, she also, based on reports from the "beach", makes the call to either send the next wave in - or to withdraw the landing force. The naval commander making that call, regardless of specialized training you mention, is quite unlikely to have knowledge of amphibious assault. In the US case, its likely the admiral in command of the carrier group in overall command - a naval aviator by trade who has never set foot (unless very unlucky) on a gator. When the Brits fought the Falkland war, the overall command of the landing force rested with Commodore "Sandy" Woodwards, a submariner whose sole exposure to something other than subs was command of the destroyer Sheffield.
[p.s.: I'm putting "beach" in quotation marks because nowadays, with AAV's, LCAC's and tactical helicopters, landings take place less and less often on an actual beach.]
All this said, we are not talking about Ottawa deciding to get in the amphibious business in the morning, getting the ship in the afternoon and staffing it the day after with soldiers, airmen and seamen that have never trained for it and sending it to breach the Atlantic wall right away. There will be time to train up to what we have to do. My points were always that, contrary to what is propounded, achieving some reasonable amphibious capability is both financially feasible within the fiscal constraints of Canada and within reasonable training in the techniques, tactics and strategies of amphibious warfare considering the the current experience and knowledge base available in the CF.
The specialized training required of naval officers serving on any amphibious ship would be part of their pre-posting training, just like we currently do for instance, in the case of the navigation officers, combat officers and any other officer in a specialized tactical position, and the Sea logistics officers of course.
I agree with the list of likely tasks of ArmyRick for such force - and that means that, if we were ever facing a "breach-the-atlantic-wall" scenario, we would be doing it in company of allies with the extra experience and materiel (combat aircrafts) necessary.
I have one more probable task (or at least possible): with speeds of 22 Kts available to Dodko/Canberra types likely for Canadian selection, you can load them with eight to ten Maritime Helicopters when not in use on amphibious operations and turn them into a useful ASW platform for convoy escort. But this is something the MH community and Navy already knows how to do.