Thus the question isn't what regulatory regime is best for squeezing the most out of LTE, but rather what's the optimal pace of radio communications evolution and how to achieve it. That's a drastically different type of question that almost certainly has a drastically different answer, or at least a much more complex answer.
Instead of just giving it away or making it all free-reign.
Whenever anyone wants to use spectrum, their device automatically bids and gets allocated whatever size slice of spectrum and transmit power they ask for. Then the device maker or the user pays the bill at the end of the year, perhaps with some minimum free amount each year per person, which could cover all except the biggest spectrum users.
If you didn't like the government allocation scheme, you could rent your own block and do your own sub-allocations, for example some kind of packetized system with microsecond long packets wouldn't want to have to contact a government server for every 1 microsecond allocation.
That gives a strong incentive to use efficient allocation schemes.
Remember, the free market is only efficient when transaction costs are low.
If I’m out in the middle of nowhere with my team and we’re using these radios because there’s no cell coverage, a) how would a given radio “bid” on a piece of spectrum, and b) how would the other units in the talk group know to listen to a particular frequency for my message?
Right now it’s easy to know whom to tell about the coordination though: the Canadian government :).
As with software patents, I think there's an argument to be made that this is no longer true. Digital modulation schemes are leagues more efficient than older analog techniques, both in terms of power and bandwidth. Spread spectrum schemes in particular are even reasonably resistant to being plopped on top of each other.
The spectrum ownership scheme allows established players to sit around on their asses using loud, inefficient modulation schemes with huge dead zones in between channels because they don't need to do any better than that.
I think radio technology would be better across the board if spectrum were open, and if people had to compete by using better, more efficient, more interference-immune modulation schemes, or risk getting stepped on by someone else. If we had a system like this, the noise floor would just slowly increase in heavily used parts of the spectrum, rather than what we have now, which is a whole bunch of legally mandated quiet zones punctuated by huge narrow carrier spikes.
The technology to do this exists... you can go buy a broadband SDR and put together a system like this in GNU radio fairly quickly for experimental purposes, but it's not really legal to actually use this anywhere.