Multi-Step vs Single-Step Mash Benefits?

Hi all. Just wondering if someone could point me in the direction of a book or resource that could clear some things up for me (or offer up your own advice). I've seen a lot of threads that explain what multi-step mashing is and what the different temperatures do, and how to manipulate the process to make something drier vs sweeter.

I'm having trouble grasping when it makes sense to do multi-step over a single-step? Say for instance I'm making an IPA, Blonde Ale or just a normal old Pale Ale. I want it light-medium body with a dry finish. I feel like I could do this one of two ways without really telling the difference. Mash at 146F for 45 minutes, then at 158F for 25 minutes. Or I could just mash around 150F-152 for 60 minutes. What's the difference? Is there a benefit to taking the extra time, effort and complication involved in the multi-step version of this?

Where I perceive the benefit lies in a multi-step mash is with something like a protein rest at 131F. That's it! Using undermodified malts for a special kind of lager. Or cramming a ton of oats into a beer. I've even noticed (I think) that even a small 10 minute rest at 131F with my ales gives a lot better clarity to the end product while not sacrificing head retention. I'd also use multi-step mashes with decoction for obvious reasons (decoction raises mash temp when adding it back in).

So that's my conundrum. I think maybe I'm missing something. But I feel like my multi-step practice lately has been a slight waste of time for some of my recipes.

 

I don't have any advice of my own to offer up being that I'm still a newbie at all-grain brewing, but here is a YouTube video on mashing mechanics that I thought was pretty helpful.
[ame]http://youtu.be/1PSvCRtVdZU[/ame]