'Mashing' grains for flavor during steeping...

Due to a baby on the way, a rough new job, and zero time, I need to brew up some low-gravity, extract w/steeping grain recipes, and back off of all-grain/mini-mash for awhile. One of my favorites is a low gravity English porter w/Maris Otter, brown malt, crystal, and chocolate malt. Can I use the brown malt in a steeping capacity, knowing that I won't get any gravity points from it? Will I still get any/all of the flavor if I do, say, a 45-60 minute steep? This way I could just do steeping grains and a Maris Otter malt extract, with no sparging, etc. Would this work or, also, are there any things that could go wrong w/this method? What about other mash-only grains (like biscuit/amber) for flavor (i.e., not gravity) only, say, for a special bitter?