That might have been the business side of things rather than any actual development, but they could at least generate ideas so it might have been useful time. As for Bethesda not being LucasArts, wait until the release date they want gets close, then we'll see.
LucasArts was a different deal, I think. They changed their minds and went for a Christmas release for KOTOR II, pushing it back. Didn't they?
If not, well. There is such a thing as getting your work done on time. If Obsidian knows when their work is supposed to be done, then they should get it finished by the deadline, like any professional.