You are the master at damming with faint praise.
I don't suppose Lamond's bright enough to have seen that franksolich already knew about the letter and its author before it was even sent (since no crime was being committed, I was under no obligation to discourage it).
Early on, I was sort of tempted to give him a few clues, but he ended up being such a dick about it that I decided he'd have to
work at solving it himself, without any help from franksolich.
He won't be any closer to solving it than he is right now, even when he reaches California Peggy's ancient age.