To answer questions in no particular order:
- Yes, of course I read the cooking sections here and elsewhere, as well as numerous books.
- I trimmed the extra exterior fat on the BBs prior to cooking.
- Total cook time is about 5 hours: 3 at 225, 2 at 250 or so (I neglected to say this earlier).
- Not sure why it's assumed I cook at above 300 on the gasser; I typically smoked them with hickory at about 230 on the gasser for about 2-3 hours after first searing them (with a Weber Genesis it's pretty simple to maintain about any temp within reason).
- I'd really prefer to not use foil if at all possible, just a matter of principle to me.
- I've always been pretty handy in the kitchen and have been gassing ribs for about five years, not sure why it's so hard to believe my gasser ribs were really good. It's not that I grew "accustomed to them" but rather they were actually really good, legendary even, people have told me my ribs have ruined them for life, other folks who previously hated ribs like mine, etc, etc. In case anyone wonders here's my gasser rib method in short: trim, let warm to room temp, rub, sear, let cook at about 300 on grates for an hour, place in warming basket then smoke for a few hours until they look just right, then sauce and lightly carmelize sauce on grill grates, all the while with a foil log of wood chips smoking by one of the burners. They are freaking good, people used to ask me for lessons and stuff.
The WSM ribs are good by all normal standards and plenty tender, just a bit more greasy than they should be. I'm thinking my original hypothesis is correct: give them an extra hour or so, maybe bump the heat a tad also at the end. In fact come to think of it one batch on the WSM only cooked a total of 4.5 hours.