I think "the club" has no official stance, one way or the other. It was decided some time ago that we should allow the discussion in an open format, and taking into account any disclaimers that may or may not be given as sort of a given.
There have been modifications that change the emissions compliance of these cars since before this internet based club was formed. No different than any other automotive enthusiast club, save maybe for the Prius Brigade.
However I think we as a community should be at least trying to understand how these things work before jumping to any conclusion that one MUST modify their car, often brand new ones, to make them functional. Which simply is not true.
Then the legal side of things, which a lot of people cannot seem to grasp. Tampering with emissions control equipment on your car, your lawnmower, your chainsaw, or whatever, is indeed against Federal law. It is stated very clearly in every single owner's manual of every single car made and sold in the USA. I am not saying myself one way or the other if I agree with this or not, that is not relevant. What is relevant is admitting you are doing it, and being OK with that. It has nothing to do with "oh, *they* don't check emissions here". Well, that's fine, but if that vehicle was sold here, it HAD to be certified for sale here, and part of that certification is that it meets whatever standards were in effect at that time.
In one way, you can look at it like tags on a mattress. Do not remove under penalty of law. Does anyone, anywhere, know of anyone that got their mattress tags checked, let alone was hit with a penalty for doing so? Didn't think so. But the other way is, if some guy is doing something in the privacy of his own home or garage, and there is no mechanism in place to check for this type of thing.... then he is going to get away with it. But if a
business is doing this sort of thing, it can be a very different story. Our shop does not do modifications like that, and even if we did, you'd never hear me talk about it here.
Now my own thought about it, at least on the 2009+ TDIs, is kind of the same way I feel about artificially low Interstate speed limits. Most people speed. You can
usually sail right past a police officer doing 5 or even 10 MPH over, along with the vast majority of everyone else cruising along with you on the road, and not be stopped. So if the law is so easy to circumvent, and there is little to no enforcement,
then why is it even there in the first place???
Unfortunately, we (the people) have legislated our way into a spot where the laws that are on the books often don't balance the whole picture. So if modern diesel emissions compliance was easier, we'd not really have many people wanting to remove the stuff. But since it is so strict, the components must be placed on the engines, and many are fragile and expensive. So they get taken off.
It is hard to argue with a guy who bought a new $50k truck for his construction business, and the truck gets 12 MPG, and randomly loses power when towing, or sets small shrubs on fire, and now wants to take the DPF and EGR systems off, retune the engine, and now gets 17 MPG doing the same work and has more power and doesn't worry about the fire department being called.
(and yes, this has happened
).