overpriced = priced higher than perceived value
Value is certainly subjective.
However, if the next iPhone is priced at $1000, it will be considered as overpriced by most people.
Same for Canon products.
What if that $1000 iPhone sold at, say, a 25% HIGHER rate than the previous model; would it still be fair to say that it was overpriced, given that so many people were willing to pay the price for it?
Of course, it's obvious where my argument is going: "Everything is worth what its purchaser will pay for it." At least this is true in the absence of market manipulation. If enough people are willing to buy enough of these overpriced
items so that it's profitable for the seller then the item is, de facto, not overpriced.
The explanation for the 5D3 price history is likely very simple: Canon thought people would pay a high price on release; many did. Then demand dropped off, so the price dropped accordingly. Will the higher price sour the perception of Canon to the point where Canon users migrate? Who's to say? If it does then Canon will change their market tactics. Canon is not my friend or spouse, I don't need them to like, love or respect me, nor I them. They're a business counterparty: they want me to give them lots of my money, and I want them to give me lots of value.