[davec]

I disagree that a classically trained musician wouldn't be surprised at the predominance of IV -> I in popular music. Plagal cadences aren't nearly as common as V->I in the common practice period, and when it is used, the pull of IV to I isn't nearly as strong. The resolution is much weaker.

[gnaritas]

Of course it weaker, but tons of two chord songs only have I and IV, it's a sound well burned into our ears. Anyone studying music theory would not be surprised by this. Perhaps I'm meaning something different by classically trained, I just mean trained in theory, not the classical period in history.

I also dislike this idea of breaking the rules, theory is descriptive of music, not prescriptive. There isn't anything you can do that can't be described by theory, that's its purpose. The rules aren't rules, they're just common idioms that people use, using an uncommon idiom is not breaking a rule. Rule is not a proper word to use.

[abruzzi]

It's a slight inversion of expectations. V -> I is more common in classical, but IV -> I is a close second. In this set of songs, IV -> I is more common, but V -> I is a close second.

[jerf]

Your "classical training" is pretty weak if your teachers never saw fit to mention that little tidbit at any point. If mine bent over any further backwards to disclaim the idea that classical chord progressions were the only ones I think their spines would have cracked.

[baddox]

Plagal cadences aren't so common, but this analysis wasn't limited to cadencial transitions.