Using MVC to handle a form is like hitting up Wal-Mart in a Peterbilt.

If you're developing a major application however (delivering the goods to Wally World), then MVC is completely the opposite of over-complication. It's a very solid design pattern, usually being built through the use of other very popular design patterns, which I would presume accounts for a large portion of its popularity.

At the very least, if you plan on developing enterprise level applications, or even just programming (PHP or otherwise) for an extended period of time, it's one of the many patterns that should be learned just to gain the experience from it. The concept alone can turn some on-paper ideas from improbable to highly possible very quickly.

I still prefer BBQing though.