I suppose it could be argued he wanted to keep Shonella on board by acting, but that was a long shot after he turned on her again (he already did so when Benji went). There isn't any real reasoning behind it however you want to look at it, it was a terrible move. But to say he voted Sharn just because he felt like it doesn't make any kind of sense. I did think that was trying to get Shane on side by not going to a tie, that would be slightly less outlandish as a reason, but that also plays into the fact that he wanted to work with Shane and so was more with her than Shonella. Again, still a horrible move because Shane has wanted him out for weeks.