The midi range, not the tweeter, is the most important driver in a speaker.

This is wrong. If mids were the most important why dont you just buy yourself a pair of ATC midrange domes and stick them on some stands and call it a day? 
That would never sound high end. 

There is no such thing as the most important driver. Every driver is equally important DO NOT BE FOOLED

Unless the integration with box, XO & other drivers  is so egregious that it makes no difference that any POS would be equally as awful.

What about a 2 way 2k XO?

They are plenty of loudspeakers of yore that only had a great midrange and are considered world class. Quads, Apogees to name a few. If you get the midrange right in a loudspeaker you may not need anything else. 

Hi everyone:

To be clear, I was trolling a bit in good humor, but also wanted to point out that we pay a lot more attention to the tweeter than any other driver.

Scanning old posts lots of people are posting about tweeter materials, type, etc. It is rare indeed when a buyer is asking about say, a kevlar vs. paper mid or woofer.

And indeed, the prices for raw drivers seem to tilt towards tweets.

I remember reading a statement from Pat McGinty of Meadowlark Audio. "The tweeter illuminates the midrange". If the two don't work together correctly, it will not matter how good the midrange driver or the tweeter is. They are equally important to each other.