Great post, Matt, because I think it highlights the issues nicely. I think you will not be surprised by my personal opinions, however.
I agree that the laws contemplate that knowledge of them (or the SO's regulations) are not required. However, what has not been previously discussed in this thread, and you are bringing it up for the first time, are the consequences of one's actions should they result in MI. In online bridge, where there is no director present, at least not one that goes around adjusting results (we know that they are available for consultation - even incorrect consultation

), the consequences of MI are unclear. Perhaps the unfettered ability for an opp to skip a hand? Then again, who rules on the MI? The partner of the miscreant? I don't know.
What I do know is that MI is a concept that doesn't go away just because one is playing online.
I believe that this puts enormous pressure on the theoretical miscreant to do things properly. I believe, although I could be mistaken, that MI is presumed whenever information is found to be incorrect. Obviously, in the case of self-alerts, this is even more of a rational position than when the MI is from the miscreant's partner.
With that said, we find that it is extremely easy, IMO. The possibilities appear to be:
1) You know your partner, and the system you are playing is "X". The information you give must be consistent with your agreements.
2) You do not know your partner, and the system you are playing is believed to be "x". (Both profiles say: "2/1 only, please"). The information you give must be consistent with your agreements.
3) You do not know your partner, the profiles give no reason for you to presume any system in particular. You must presume to be playing BBB and you must answer consistent with that system.
Now, what happens when things get bolluxed?
1) No problem. You had clear agreements, you disclosed them, and your bid is either consistent with them or it isn't. If your explanation is consistent with your agreements, there is no MI and everybody should be happy. If your explanation was not consistent with your agreements, however, I have no sympathy for you and whatever the SO says should be your punishment is ok with me.
2) I don't see any difference between (2) and (1) here. You know there is a system and you should answer predicated on that system.
That leaves us with:
3) Ah, the problem child. If you assume you are playing BBB and explain accordingly, fine. However, if your bid is inconsistent with BBB and you were just trying to mess things up (a pattern would be necessary to establish this) for your opp, I would think MI would be the charge. But let us take the more difficult case of the poor ignorant soul. First, they try the "no agreements" answer. Then, after being told that such is not acceptable when dealing with that specific bid they are presented with a quandry. What to say? Let's say they don't know BBB, and, flustered, just say "natural, opening hand". Of course, we are talking about a 2D bid here, so just about everyone knows that can't be the case. No matter. They provided MI and that is the way the ball bounced. How do they avoid this? Well, they can do so by describing the meaning of the bid, as they intended. That is, in the absence of a verifiable agreement, when dealing with bids that would normally be defined by a typical and properly filled out cc, the only way they can protect themselves is to disclose the meaning as they intended.
I believe there is precedent for this. I believe, when using screens, if there is actually no agreement, a finding of MI cannot be made if the individual explains the intended meaning of the bid. I would be hardpressed to recall the writeup where that took place, but maybe somebody who follows the appeals writeups might be able to do so.
I know that others are aghast at my attitude regarding this, but I really don't find it all that complicated, nor do I think it all that problematic for anybody who is interested in playing a fair game.
I'm all for using the laws of bridge to one's advantage when the circumstance presents itself (ahh, for the days of penalty cards). Doing so within the confines of the laws is perfectly acceptable. I would never decry a bridge lawyer, if you will, from hoisting me for a hesitation.
But disclosure of bids is something I feel pretty strongly about and I do believe that the framework already exists to deal with it fairly.
Now, if only the yellows would understand things and if the technical naysayers would change their tune, we could get on to bigger and better, like how to implement it in a fair manner and how best to go about communicating it.
Will it be a somewhat slow process to fully implement? Maybe, but most of that is because of the attitudes that people have brought with them from f2f.
Welcome home.
George