I do know for brewing that Bunn had a restricted flow shower head for decaf beans for their BTX coffee makers, I believe that it was to prevent overflow.
No doubt. It is interesting how different decaf behaves. It definitely passes water more slowly than regular coffee. I have one hand grinder dedicated to grinding decaf beans, as a result. It has nothing to do with not wanting the decaf beans to sully the other grinders. It's just that I need a slightly larger grind size to get the water through the the decaf grounds in roughly the same amount of time as the regular coffee grounds.
One thing I like about the Klatch Decaf Colombian Las Serranias is that the grounds bloom in more or less the same fashion as those from freshly roasted regular coffee beans. In general, however, decaf grinds tend not to bloom very much, which makes them seem stale or flat even when they are freshly roasted. I suspect that decaf similarly produces less crema in an espresso extraction.
That alone would turn a lot of Home Baristas off. You could be pulling the "best" shot the beans allow, and still not getting a good looking shot. Brewed decaf coffee is certainly more forgiving aesthetically, and probably doesn't accentuate some of the undesirable flavors the way espresso might.