Tough, just not cooked enough. Go ahead and overcook a slab (fall off bone) then back down cook time just a little. Fine line between fall off bone and undercooked.
Spot on advice.
I think returning sauced ribs to the smoker for longer then 10 minutes causes a tough layer on your ribs. Just my opinion.
Learned this after lots of trial and error.
Try cooking on just one pit as another mentioned till you get it consistent enough for your liking.
Again, spot on. Learn how to cook them on one pit, master it and stick with it.
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