Does changing post title effect SEO?

[Simi123]

Changing your title can do one of three things:

1) Hurt, as in not ranking for intended searches.
(You rank really well for student loans, but change the title to stupid loans.)

2) Help, as better ranking for searches of what it should be.
(Your title is on stupid loans, but you want student loans and that's spot on.)

3) Nothing.
(Your site was not ranking, so what the heck?)
Or
(Your site was #5 for student loans in the fall and you changed in to student loans in October. No movement)

So everybody that answered blindly, "yes," "no," or "maybe," YOU ROCK!