I think he said something like "let's face it, we butchered the songs during the BIA tour". I love the BIA tour, but it was pretty extreme in stretching the songs: expanded to death, breaks, synth and sax all over the place, 100 chords when the studio version had one... Ok that's why live is for, having fun with the songs, but this was a bit over the top. Jack fitted this mindset of the time, he had fun playing with the songs to the extreme, like his controversial solo on Wild west end, some love it, some hate it...
So yes, he is not my favorite 2nd guitarist either, even though he was lovely and great fun. David had a unique groove, Hal was competent, Phil was ok, Richard is by far the very best, and Jack... well, was over the top. That was 1985, he was great for the period. But I can understand that Mark wanted a change...