The DC is tiny
I don’t think it’s fair to say it’s downfall is that it can’t really cook a full packer. Perhaps it limitation is that it’s not well suited for that. After all, it’s tiny and pretty cheap and considering all the good things it can do and all the included features - it’s one of the best smokers out there for 1-2 person cooks.
Just my take on it

Can we agree on the word limitation?  JaJaJa...

I would think even for 4 adults...2 whole chickens will feed 4 people, or 4 steaks, 8 brats, 4lb ham...it really is more suited for 4-6?

Well when I made the Brisket I spoke of earlier, that was for 7 people. While the brisket rested I made the beans, mac and cheese and pig shots.
Do I wish I had a bigger unit and one that was the height of a normal size grill? Yup! But in the end it worked and everyone went away happy and full. 

you could probably rig up some tinfoil to place around the edges, to act as a heat shield...   

Not sure I've ever seen a 12 pound packer... but I suppose you cut off the thin end of a flat and maybe squeeze one in that was  originally larger than would normally fit.

Well, I did actually see a 11.5 pound packer this weekend... In fact I bought it.   I still would have had to trim it quite a bit to fit it in my Davy Crockett... I chose to just do it on the Fast Eddy.

Well mine started at 15 but after trimming was around 12. I also had to use upside down bowl in the middle and it still was almost touching each end of the grill. After a couple hours removed the bowl and it was fine for size.