What does winning a presidential nomination show about a candidate's skills?

[Mister Mets]

This forum has a few hypothetical match-ups, and discussions about how effective potential presidential candidates would be as their party's nominees.

But this seems to neglect what winning a nomination would reveal about a candidate's strengths.

For example, a small-state Governor is a terrible candidate for President.

A small-state Governor who wins a tough primary might be an electoral powerhouse. See Bill Clinton in 1992.

A discussion about Christie Versus Clinton isn't comparing the two right now. It's comparing a Chris Christie who won a tough presidential nomination, and has likely gotten a lot of good publicity to a Hillary Clinton who isn't in the same position she is in now.

A related factor is that some nominees can win the nomination by pandering to the base. It doesn't suggest they'll be strong in the GE, any more than Goldwater was in 1964, or was McGovern was in 1972.

But how should we take all this into account?