You better bet your boots on it. That stuff is crazy. Just like us-05 and wlp001. Your best bet is upping your specialty malts if you want extra sweetness - but make sure they arent too dark.
Americans use CaraPils and Crystal 15 - 40L 30 - (80EBC) around the 10% mark in total. Some go higher... but you can taste when you've overdone it.
Yeah, I find 1056 to be a maltose mowing monster, particularly on 2nd or 3rd generations. That bit of CaraPils should fill it out, and get you great head too (according to Joking)!
I brewed Yakima Monster again on Sunday with Golden Promise. The #1 original recipe from the start. I'm thinking about dry hopping with half as many hops as the recipe calls for though. Not because I'm a tight arse... but because of the value of seeing what impact this has on the flavour of the beer.