[spoilers] Harry and Lucas

[almh]

It will be interesting if we ever find out who sold Lucas to the Russians, and to see the effect it has on their relationship - I think we could be building up to something like that because we've had quite a big emphasis on Lucas's time in Russia. That could prove interesting...

I think it just meant that Tom was there when was, I don't think it implied anything much. I think the writers just added that in for the loyal fan, a link to the past that didn't really require much explanation for those who had never seen it before.