Bruce seems to have had bad luck with the knee issue causing a DNF before, IIRC. While I find his attitude to the record ratifying authorities perplexing, I don't wish the man ill and I'm sad for him that things aren't now going so well. I hope that if he indeed abandons he can get the knee problems sorted out permanently, and in the meantime take note of the criticism and get the ride sorted out properly in all respects before having another go. He's obviously a strong competitor, and deserves to have a proper go at this.