I think it would have been very interesting for Desmond to have seen Libby on the island. Just like it was a shock for Jack and Desomnd to see each other on the island.

Would Desmond have been automatically suspicious about her. I don't know, but it is a pretty big coincidence for them both to end up on the same crazy island. And any conversation they had would have at least the potential for it to be an interesting one.

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Doctor playing golf. Woo, boy howdy, now I've heard everything. What's next, cop eating a donut?