I have typically used single temp mashes, but after listening to some of the commercial brewer interviews on Brewing Network, I have begun using a short beta rest in the upper 140's and then a quick ramp to a alpha rest temp. My first brew with that mashing approach is in the fermenter now, so I don't have a feel for the effect yet. I fully expect that the fermentability will be higher.
This is something that I would like to start doing. I feel the body of my beers is a little thin and one-dimensional lately. Not sure what it could be but I'm wondering if doing a small step mash might help.
I also think a 90 minute, at minimum, boil will help create some depth to the flavor of my beer. Let us know what you think of the step mashing you just did when the beer is done.