Well I'm terribly terribly sorry for daring to think out loud lol. I merely suggested one of several potential reasons, my initial comment supported your comments but I guess you missed that one
Demand surely outstripped supply and a likely reason for that is poor forecasting. Not the only reason, and given you provided no supporting facts I fail to see how any of the comments, yours included, is anything more than guess work (well it is a rumours site
Doesn't it contradict your poor forecasting suggestion that years after production started they are still not making enough? Yes in some ways it doesn't make much sense to restrict supply, however a certain german car maker has been restricting supply to some models for a long time and as such has cars which appreciate after being sold. There are reasons for doing it, it has been done and it will be done again in the future. I have no idea if this was the case with the 5d2, I was just suggesting some possibilities.
Perhaps you should suggest to canon they sack their sales forecasting team given after 3 years they cannot reliably predict demand.
The ps3 and bluray drives were a perfect example of supply outstripping demand due to new technology being hard to scale, however in the face of demand productivity did scale. Just look at the iphone and how easy it is for apply to massively increase production every quarter (11m-14m-21m or something equally silly, they are allegedly ordering an extra 6 million cdma units for Q1 2011, thats a serious bump), it can be done in some circumstances (the ford s max is an example of it taking forever to ramp) under the right conditions.
Given canon must be making money on a unit basis, you have to admit that they should be able by now to keep the thing in plentiful supply unless perhaps there is another reason? Unless they have diverted capacity elsewhere (they have added extra tiers, I have lost count how many different tiers they have these days)? Again, not intending to offend any sensibilities, just thinking out loud.