That sounds logical, but I'm pretty sure (like most info regarding the mechanisms of carbon dosing) that you are speculating. I've never even heard people selling carbon-dosing products (going as far back as AZNO3, at least) claim anything like that. Definitely would not apply to bio-pellets.
It's not carbon dosing per se, but the need for it, that indicates the imbalance. The question to me is whether carbon dosing is as good as other options when all things are considered. Which makes it a problem that we don't have all the info about carbon dosing to consider
And how to define balance is an excellent question that gets asked all too infrequently. There's no one correct answer since everyone's tank is a little different, but I think I've got a pretty good - at least very useful - one.
If your animals can live happily (which I can only honestly measure in terms of lifespan) with minimal to no water changes, their biological processes can be considered "in balance" with your live rock.
Once your animals exceed this balance, nutrients start accumulating - pollution begins, your tank is out of balance.
This is easy to understand and easy to use:
- Buy a tank that's big enough for your animals to properly grow up to adult size in, then they will live easily to ripe old ages.
- Done this way, not much specialty gear is required and your main interaction with the tank will be with the animals and feeding rather than other things. Not only that, your tank will be more resilient and you'll have more money in your pocket. Spend it on a bigger tank!

The biggest problem is that most people blow by this option on the way to the gadget/chemical aisle without a second thought.
The Berliners figured out back in the 1970's that all your really needed was a source of flow, live rock and a skimmer.
If anyone can remember what it was like before the Berliners methods were brought over here in the 1980's, modern times are starting to look similar. To me, anyway. Hi-Tech!!
There aren't many good, complete explanations of the Berlin Method still out there that include the history, so a third party link is called for:
Link. (Keep in mind what is considered a "big" skimmer and "bright" light are what pretty much everyone uses these days.)
-Matt
P.S. I forget if it was you, but someone mentioned a lack of increase in bacteria in the water column under carbon dosing. The bacteria grow in mats on surfaces - they are not generally free-floating when alive. Even when they are in the water column, more than likely it'll be as part of an aggregation of marine snow, not just free floating.
P.P.S. Just trying to add some meat to the discussion....hope all this isn't perceived as all negative! Keep the discussion going!