Is Catalog & Library Function Mandatory in LightRoom 4?

The reason for my asking is that I want to use PhotoMechanic to ingest, sort, rename and the file my images.

My ignorance about PP will show here. But it appears to these novice eyes that running LightRoom turns over the archiving of your images. And it appears the process is complex. I want to use it just for retouching and RAW conversion and a few other manipulations.

I want the program, but just as a Saturday night date. No marriage intended.