Here's a quote from a fabulous article on the subject that really drives my point home:
"The contract theory of license also creates obstacles and confusion in other contexts. Some copyright owners - as exemplified by the open-source and Creative Commons movements - wish to grant nonexclusive licenses to large classes of users with whom they cannot bargain and from whom they seek no payment in return. 21 Contract law provides an ill-suited basis for such dealings. 22 For their part, members of the public who understand licenses to be contracts are also likely to believe (erroneously) that their use of copyrighted works is restricted only by express license terms and only if they expressly agree to be bound by them."
ARTICLE: A License Is Not a "Contract Not To Sue": Disentangling Property and Contract in the Law of Copyright Licenses, 98 Iowa L. Rev. 1101, 1107
I read the introduction to that article. The second sentence after n 30 is
The role played by contract in the realm of license is a different one - it provides a means for licensors to protect a licensee's interest in non-revocation without granting an ownership interest in the property.
That seems to me a fair description of what most people have understood the OGL to involve. A few sentences on, the author says
There is no reason, in principle, why copyright law, like land law, should not permit the creation of irrevocable and exclusive license interests by means of either property conveyance or contract, leaving each to be enforced through the appropriate means. A clear recognition that copyright owners are able to create irrevocable, nonexclusive licenses by unilateral deed would be particularly helpful to owners who wish to grant open-source or Creative Commons licenses.
I don't think this contradicts the idea that the rights and powers granted under the OGL may be irrevocable, even if WotC were to rescind/revoke its (hitherto) standing offer to license to all comers.
Here's another quote from a federal court:
"A license by definition is not a permanent entitlement and does not operate to create an estate in land in the licensee. It merely constitutes permission to do certain things on the licensor's land. The licensor ordinarily can revoke it at any time, with or without a reason..." (applies to land, but the concept is the same).
Kapadia v. Chi. Transit Auth., No. 87 C 1919, 1987 U.S. Dist. LEXIS 4156, at *4-5 (N.D. Ill. May 15, 1987)
This characterises the nature of a licence as a non-proprietary interest. Which I think everyone understands and agrees with.
But surely it is possible, by way of contract, to bind oneself not to exercise the power of revocation? What the remedy would then be for purported revocation - a voiding of the purported revocation, or damages for the consequences that flow from it - I don't know, as far as US contract law is concerned.
Because no other lawyer on this thread has cited a single source to support their arguments. I am the only one.
Well, I think the passages from the Iowa LR article provide support.
Of the cases you linked to, the only one I looked at is the Mueller one - which concerns oral licences giving a right of way to neighbours, and is primarily concerned with whether or not they can give rise to an easement by way of long user. It doesn't seem to me to have much bearing on whether or not a contract with the intricate written terms of the OGL can bind the parties not to revoke. The Court, at 33, even allows that "the agreement that the mutual use was to continue "as long as both houses stood" might give rise to a claim that defendants' revocation at this time operates as a fraud upon the plaintiffs" - but puts that matter to one side, as even so that would not establish the easement the plaintiff sought to claim.
I'm not saying that you are definitely wrong, but I'm not seeing how the two sources you point to that I've reviewed support the claim you're making. (It's late at night where I am, so I'm not going to check the other sources. Do they bear more directly on the issue at hand?)