True. By no means meant to imply that the OLC memo settled the question. Simply that some smart people had given it thought in a somewhat formal way (as opposed to newspaper columnists waxing wise) and produced a good recap of the questions (and, more helpfully references to similar activities from outside the executive branch) regardless of the merits of the conclusions.
The Framers would, I think, be appalled at the thought of a President pardoning himself, but the Constitution does not explicitly forbid it, and the courts have historically given great deference to the President in his use of the pardon power. It could certainly be a basis for an impeachment proceeding, however.
Two Staff Reports and some previous threads that may be of interest: