I used to have my own IT company and now work on the biggest & most complex digital programmes in the UK.
I also deliberately chose the PAH option because:
(a) I know with 100% certainty that it works. Therefore little risk.
(b) No system changes should have needed to ensure it was workable, therefore little risk.
(c) I know City's record on introducing change to the detriment of the fans. Big risk.
In IT, one of the primary drivers in the implementation of new technology is ensuring you mitigate known and potential risks. City ignored that concept but just about seem to have got away with it yesterday. A lot of that was seemingly down to some excellent contingency planning, so they should be commended for that but they still took an unnecessary risk.