Making global generalities off of literal rubrical foot-faults.
I could be he has arthritic knees that periodically flare up. I "get" this because I have R.A. myself. If I genuflcted, let alone knelt in church, it's doubtful I could get up without a stout yeoman to hoist me right and left.
There are things you can well criticize about Pope Francis. I don't like his appointments, many of them. I don't like his insouciance about stuff like the Scalfari "interviews." But don't pick a something that might be more about tendons than theological tendencies.