You want a custom stain job. There is no one single accepted way to accomplish what you want. Some of us use aniline dyes followed by Ebony or a custom stain mix. Some sand to a certain level and then waterpop the floor to open the grain to accept more stain pigment. And then, some have resorted to a paint slurry as a staining media.

You may want to search the archives at Floormasters.com for staining tips, but you really ought to be looking for an artisan who knows how to produce what you want.

Floormasters is a professional site, so keep that in mind should you pose a question. Searching the archives is no problem...however, annoying the professionals over there with time wasting questions from, especially by DIYers, is not tolerated well. There's plenty of information in the archives, but do your own search should you go there.

Here is a link that might be useful: Floormasters

Dark floors are more labor for a flooring pro to achieve, and consequently are a more costly job for the customer over a "standard" one coat stain non custom job. White oak has greenish undertones as do most "ebony" stains. Red oak is usually more successful at being stained dark without as much green tones. Both white and red oak are much better at accepting dark stain than birch, which can be blotchy and is softer. I also prefer General Finishes over anything Minwax. I find that more hacks than not use Minwax and shop at box stores. If that's what your flooring professional is doing, then perhaps he's not such a pro.

A mix of 2/3 Espresso and 1/3 Brown Mahogany (or sometimes Black Cherry on white oak, or Ebony and Red Mahogany for Minwax if you can't get GF), waterpopped, 2 coats, has been a successful recipe that I've used for clients in the past on oak. But like anything else, a bit of trial and error is involved due to your own home's lighting conditions, specific wood, and the workman's practices. Understand that I'm a designer with lots of DIY under my belt, not a flooring professional. I do collaborate with flooring pros to achieve a specified look when I'm working on a reno for a client, however, and I have learned enough to make my own projects turn out well.

Thanks for the very helpful feedback! I'm passing this along and will update soon.