History never PROVES anything. It simply indicates patterns, which may or may not be relevant to the present. Recent history indicates, as I've already pointed out, that VPs of successful 2 term presidents who run to succeed them do well. Since 1960 there have been 3. One was elected. and the other 2 narrowly lost. Gore actually won the popular vote. So only if you ignore any distinctions between past examples and paint everything with a general brush can you deduce that being a VP is necessarily a path to obscurity. And btw, Ryan is much more likeable person than Nixon, Bush 1 or Gore, and if Obama proves nothing else it's that likeability is indeed a factor in the voting decisions of some of the voters.That's fine, and perhaps this will work, but history proves otherwise.
I also think you are selling Ryan well short on his decision to run for VP. As one of Ryan's constituents for as long as he's been in Congress, I'm probably a bit more familiar with him than you or anyone else here. Remember that earlier in the year when he was being talked about as a possible VP candidate, he rather definitively said he wasn't interested, that he felt he could do more good in the House. Trust me, he wouldn't have changed his mind without being promised a prominent role in the Romney administration, far beyond breaking ties in the Senate. I think if Romney/Ryan are elected, Ryan will redefine the role of the VP as much as Dick Fosbury redefined the technique for high jumping. Paul Ryan is not the kind of man who would consent to being shuttled out of sight. I believe, to the contrary of your cynical view, that the choice of Ryan is a powerful message from Romney that he is, indeed, serious about changing things in Washington. Disagree if you wish, but I trust Ryan's character and will a lot more than your opinions.