First usability. Having to scroll through the whole range for every band is cumbersome. Also the order of the bands gets quickly turned upside down and twisted. I also doubt there will be more people who need more than two filters below 150 Hz.

But the main reason is that processing low frequencies needs higher computing accuracy than middle or high frequency ones. This is especially true at higher sample rates, and the ADI offers extremely high ones. We therefore had to take care that the EQ will not overload the DSP in such cases, which is why there are just two lower bass bands in the EQ.

I wholeheartedly agree with Wanderflake, and I'm fairly certain that a lot of people need more correction in the 40-200 range
than in the 200-500 range. Would it be conceivable as WP is suggesting to have a "DSP friendly" 4band mode with the 2 middle bands being completelly free to operate below the 150 limit?

I have indeed the latest firmware and still would greatly benefit from the 3rd and 4th band not having restrictions. 

Example, in the room I'm in right now, Ideally I would lo-cut at 40, boost around 80, narrow cuts at 130 and at 180

With the present restriction, this is impossible to do. The workaround I found was to use the bass boost to replace the one I would normally do with the parametric EQ and combine the 2 EQ's. but it's not ideal, both in range, and in sound.

It was like that from the beginning (you misread the first post which basically states this too).

For room modes, it is the easier way to use this
http://www.dspeaker.com/en/products/20-dual-core.shtml
With included microphone and automatic calibration - without try and error - perfect adaption in 5 minutes

Meanwhile wishing for this feature being implemented, at least for lower sample rates, I can recommend trying the dual EQ mode and notch the worst peaks on each speaker separately which for me gives a cleaner sound than Stereo EQ and it reduces the need for more bands since my speakers have a little different placement and therefore resonating the room at slightly different frequencies. Using this handy little sine sweep generator http://www.szynalski.com/tone-generator/ its easy to find the notes.

Worth a try..

Just my 0.1 cents

/J