He plays that EB-1 even though it is fretted and he loves his fretless Warwick. Call that devotion. Any brand worth its salt would have built him a signature EB-1 for the Cream reunion, just think how much effort Warwick puts in to please the man, they have just built a perfect replica of his Thumb bass for him - at almos 50.000 bucks a piece (it's made from the last pieces of old rosewood they could legally find and use, it's a limited run of three using up all that wood, one for Jack, one for the Warwick museum and one for an American collector willing to pay that much).
In contrast, "clueless" for Gibson is just right as a description.