Hiya-
He lied because he hadn't told Alma about the fact that he was on that mountain with Jack, not alone. He never told her that he was there with Jack. If he had said "we herded sheep together on BBM in '63" then that would have set off alarm bells with Alma. Second, he might have thought of this excuse so he would have an excuse if he would want to go up the mountains with Jack again (real quick thinking of him).
Does this make sense?
Mel
