Hmmm, I see the validity of your argument here. I too would hate to see a sudden 180 from a character whom I think has been consistently portrayed so far.
However, I did feel during season 3, Lee's attitude toward cylons has subtly shifted. No question about it, when he devised the strategy to eradicate the 7 models, he did not see them anything other than machines that had gone awry, and they are the enemies that bent on destroying the last remnant of human race. But that was at a time all the way back when the fleet just escaped New Caprica. Up till then, Lee had very little interaction/contact with any of the cylon models. Even though Adama had made Sharon a Colonial Officer, she was under his command, not Lee's.
By the time Take a Break from All Your Worries happened, Lee has been back acting as CAG for awhile, and most certainly, worked with Athena for an extended period of time. Likely he still doesn't trust her completely, but I think his opinion of her/her model has changed. Otherwise, he would not have asked Chief if he ever wondered what might have been (with Boomer). I've always felt there's this subtext with that question--Lee was giving credence to the thought that Sharon/Boomer was more than a machine, that he tenuously considered her as a "woman"...
Back to this promo clip, I feel it is taken out of context. I'm not sure Lee's no longer viewing Cylons as the enemies. He's merely saying he's grateful that his loved one had came back from the dead, and he's inclined to get whatever he could get. I have to admit this feeling may not be most stalwart, but it is very human.
And don't get me started on Starbuck back from the dead... :\