Can erasing your iPhone's memory improve performance?

If you erase and restore your iPhone, does performance improve?

I won't bore you with the gory details, but recently I had cause to erase my iPhone. And by "erase," I mean venture into the Reset menu and tap "Erase All Content and Settings."

Leading up to this, my iPhone 3G was running like a snail through molasses. In recent months it had grown weirdly sluggish. I'd pick up my daughter's iPod Touch and be shocked at how much faster it was.

After the nerve-racking process of wiping the 3G and letting iTunes restore the backup (it was the first time in a year of iPhone ownership that I'd had to do this), I noticed something: It seemed peppier. A lot peppier.

I'm not sure why, but this definitely begs the question: Should iPhone owners perform this step every few months? Does the wipe-restore process somehow defrag the device and thereby optimize performance?

I honestly don't know, but I reckon you, our brilliant readers, can offer some insight. Am I crazy? Imagining things? Or right on the money? (That'd be nice for a change.) Share your thoughts in the comments.