I agree with this point. Not defining a main is in effect enacting a merger in the market. Not having that merger recognized structurally creates tensions which aren't either useful or productive.
No, it isn't. In the real world companies list on two or more exchanges all the time and they just sum the votes. I could probably give you six examples without even thinking, such as coeur d'alenne and first majestic for starters.
You're comparing apples and oranges.
What we refer to as exchanges (BTC.CO, Bitfunder) actually fill a whole bunch of different functions (exchange, broker, registrar, company bulletin board etc).
In RL an exchange has basically nothing to do with voting - voting would be handled by the company directly. One body needs to track and record the results of votes. If Carnth wants to do that off-site and record/publicise results somewhere else then that's fine - but remind me of the benefits of NOT having total votes recorded on either exchange?.
But that doesn't address the issue of investors on one site taking on part of the risk of default on the other exchange which they neither use nor, in the case of current BTC.CO investors, were even aware before they invested was a risk they were expected to take on in return for no benefit to them. Obviously if current investors vote to accept that risk (and any dissenting are bought out at full value) then that's fine.