I placed a few samples of white oak in an airtight rubbermade container with a small plastic dish of aqueous ammonia, I left this to sit for 6 hours then removed one piece. I removed another piece after 12 hours but noticed very little difference in the color so I replaced it and left the rest for another 12 hours, 24 in total. You can see the difference here, with no fuming, 6, and 24 hours with not additional finish.
These are the peices finished with a coat of Brown Mahagony Gel stain, two coats of 2lb cut amber shellac, and finished with a coat of dark wax. I liked the results but I have to say that I like the way the dye/stain combination contrasts the ray flake as opposed to the fuming that tones the differences down. You can see in the 24 hour sample that the ray flakes are almost invisible.
One of the problems with fuming white oak is that the sapwood will not turn as dark as the heart wood, whereas dying lets you equalize the differences. If you look at the picture on the left you can see how much lighter the sapwood is in the left and middle picture compared to the sample on the right with no sapwood.
I think after this experiment I've found that fuming is no easier than dying wood and the toxicity of the ammonia makes me want to stick with the water based dyes. While I do have to sand the raised grain after dying and I wouldn't have to after fuming I think that the tradeoff of having to time the exposure to the ammonia is more inconvenient. My method may be less authentic but its also less toxic and easier to control the color. From what I've been able to find out I don't think that the Stickley factory uses fuming today to color their furniture either. Fuming may have been the state of the art in coloring wood in the 1900's but today we have other choices.
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