Absolutely essential for first year college students, and yes, ignore that voice in the back of your head ("I already know this stuff," quoth the ego). You should read this book. It's the only grammar book you'll ever need to read, then you can let your ego out.
Morenberg builds on each foundation in each chapter, and as he progresses through the chapters, he slowly gives you more complex information, bit by bit, building, but only after laying the foundation on top of less complex terms and structures. Morenberg literally makes grammar easy because he doesn't plunge right into the jargon and platitudes ("write clearly," "don't use passives" (what if someone doesn't know what a passive is? How can that person avoid it?). He avoids that approach, and EXPLAINS everything you will need to know before you can jump into those platitudinous books on writing.
If you are uncomfortable with grammatical terms, jargon, and the like, seriously read this book. You'll feel like a god after. Then move on; because if you think you "know it all" already, you probably don't.