The best way of seeing how things happen is to get yourself on the game and see a scene as it happens. A member of staff will be able to summon you to a scene being played or you could take on a Cameo (trial) character and give the game a try yourself.
Busiest around 4pm EST onwards if you want to catch one, I think, if you're interested
I dunno, that does seem pretty feasible. I do wonder how he managed to survive the poison of a viper pit for however long it took him to get from the Boneway to the Stormlands, though. I thought snakebites could kill you in hours, not days?
Any character that is a Feature character is not played because they are characters that appear either in one of the books or in the notes admin have from GRRM. The example of Lord Leowyn on the AMA being one such instance where I managed to squeeze a little info out of their notes from something that was cut from the books
Only in very rare circumstances do Feature characters appear in roleplay on the MUSH because they are canon, and admin don't want anything they are involved in to against established (or yet-to-be established) canon.
As for the Black Aly observation... if in doubt, go with the information provided in TWOIAF. I know that when they came to update the MUSH, a few of the canonical characters had to be squeezed into already existing trees (for the sake of certain Player Characters not being written out of the game) and I think this might have been one such instance.
Hopefully Ran may swoop down into this thread and give you a more definitive answer on that front.
Yeah, admin changed the characters in the MUSH to reflect the info they got from GRRM for TWOIAF. Back in the old days of, er, last year or something, Tinessa was the late Lord Tully's only living child and became head of House Tully after his death. Her husband (and Lord Protector of Riverrun, I believe he may have been titled) was Ser Patrek Vance. My character was one of Ser Patrek's old squires.
That all changed when they changed Patrek to Lord Kermit and had Tinessa be the one from House Vance. We had a good old laugh about it at the time, couldn't believe GRRM decided to give them those names.
And yeah, there's also a Ser Oscar Tully on the Tully family tree too.