Re: Question: how should addTrack work in relation to createOffer et. al.?

Just adding my basic thinking here:

The absolute requirement I have is that the sequence (if no other
addTracks are done)

  pc.addTrack(X);
  pc.createOffer().then(offer)
  pc.addTrack(Y);

always give the same number of tracks represented in the offer. And I do
mean *ALWAYS*.

My aesthetic preference is that X be included and Y not be included,
because I think that's the "least surprise" method. But I'm willing to
compromise on that if someone convinces me that it's a significant
burden on either users or developers to make this work in all cases.

(calling out to the Hierarchy of Constituencies: the burden on spec
writers is *not* a significant consideration, unless all other
constituencies have flagged "don't care").