D’oh. I only thought the rest of the comment and then submitted as it was because I needed to go find the text to copy.
And from the 12th amendment:
But no person constitutionally ineligible to the office of President shall be eligible to that of Vice-President of the United States.
You can only be elected president twice. If you serve more than two years of someone else’s term you can only be elected once. If you can’t be president you can’t be vice president.
So if you’re elected once, then serve as VP and the president goes away and you serve as president for 2 years and a day, you’ve already been elected once so you can’t run again, and you can’t be VP because you can’t be the president.
If you’ve been elected twice you can’t be VP, so you can’t get any extra time that way.
I feel like if we get to that point, we’ve given up on the constitution. “He can’t run for president because he’s term limited, but he’s still eligible to be president, therefore we can make him vice president so the president can resign and he can be president” is such an abuse of the term “eligible” where you turn “cannot be elected but otherwise good to go” into “eligible to be in the highest elected office in a Democratic government”.
If the way it’s written isn’t clear cut enough then the court would find a way to say anything wasn’t clear cut.