That was a lesson in how not to do things.
The Royal Navy didn't want to risk it's capital ships so both the bombardment and subsequent gun support was woefully inadequate.
The Royal Air Force was both late in its arrival over the beach and didn't commit nearly enough aircraft to both maintain local air superiority and support the troops on the ground. That ultimately resulted in the creation of much better tactical air force operations.
The British army planners didn't incorporate enough intelligence regarding either the defenses or the beach conditions, and didn't focus nearly enough on strategy for taking a defended harder supported by artillery. The inability to even get their tanks off the shale beaches with steep slopes or cliffs inshore of the beach was an example of utter stupidity in intelligence gathering and planning.
The Canadian troops fought very well with what they had, but suffered horrendous losses. However to be fair, it's often forgotten that such a high percentage of Canadian troops were used because they'd been sitting around for two years and had seen almost no action. Both the Canadian commanders and government wanted Canadian troops to be used in large numbers at Dieppe. In short, great troops, poorly led at the (British) high command level.
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It was in short a "combined operation" in name only with way too little cooperation, coordination or communication.
