The original modules were designed when the PC had one slot for each effect type similar to how the PX-64 and VX-64 work. With the introduction of X1 Producer Expanded, the architecture of the PC changed. PC modules made after X1 Producer Expanded can have more than one instance in the PC but they do not work in the original X1 PC. The QuadCurve EQ is even more a special case as it acts as the replacement for the per-channel EQ introduced before the X series.

The idea is that you have a bunch of simple controls directly accessible without having to open the plugin. But I agree with you, I find it an unnecessary addition and complication. 90 percent of the stuff I use doesn't have its own PC module and using endless custom fx chains is tedious. In addition, with the QC specifically, I find the idea of having to use my mouse to turn a virtual button ridiculous and not ergonomic at all in a modern DAW environment. Which I'm only saying because it means the rather large GUI part of the QC in the PC is useless to me. I haven't counted them but that's a large bunch of controls I never need.

Sanderxpander
...  the rather large GUI part of the QC in the PC is useless to me. I haven't counted them but that's a large bunch of controls I never need.

 
Amazing how subjective it can be . The GUI of QC is so very useful to me.
 

Still off topic, but LP64 with a spectrum view and maybe a little bit " user friendly " gui would become a kind of ultimate linear phase eq....
Cheers.

Afrodrum

Sanderxpander
...  the rather large GUI part of the QC in the PC is useless to me. I haven't counted them but that's a large bunch of controls I never need.

 
Amazing how subjective it can be . The GUI of QC is so very useful to me.
 

I use FabFilter Pro Q2, it's so ergonomic that it has made me dislike knobby EQs (in software).

I've always used the Quadcurve for hi and lo passing plus whatever cuts I need. For boosts I like to insert the Waves VEQ3 after it because its boosts sound so much sweeter, even when boosting as much as 8dB. But that's an analog emulation which adds character. Other times I'll use the Waves Renaissance EQ, although its interface is horribly dated.

Just recently though I've started using Cytomic's The Drop, a wonderful analog filter emulation that has a ton of creative modulation possibilities. It's a really amazing sounding filter which has a handful of different emulations. The reason I'm substituting it for the hi and lo pass filtering on the Quadcurve is because it has a resonance control and I'm finding that a higher cutoff resonance is helping certain elements stand out in the mix, and also for electronica styles hi resonance filter sweep capabilities are a must. You can also drive the filters for added character. I'll still use the Quadcurve for my cuts however, and the spectrum analyzer is invaluable.

scottfa
Seems to me that the pro channel itself is the problem. It just looks like an artificial construct for sales purposes. Can someone give me some benefit of using the pro channel over just having the plug ins placed in the fx bin? Keep the plug ins proprietary. Maybe i am missing sonething that would make the obvious work flow issues worthwhile.

I like it from a workflow POV. I have the inspector floating and changing track focus automatically changes focus to that track's PC.
 
Helps to keep the work space a lot less cluttered as well, although that situation has improved with the ability to pin FX. Still saves a lot of clicking though.

Sanderxpander
I use FabFilter Pro Q2, it's so ergonomic that it has made me dislike knobby EQs (in software).

 
I second the FabFilter Pro Q2.  One of the features I like is being able to listen to what your filter out. Good for general band pass filter and to filter some bad vibes. (Ah there's that critter I'm looking for!)