The more I think about it, the more of a problem I can see with onboard ticket sales.
Now, as it happens I do carry a copy of the NRCoC and the Byelaws with me in my bag, but they are not take away copies for passengers (although I am happy to show them to people if required), and as I carry lots of other paperwork with me my bag is already full and weighs a ton without having to carry any more stuff around. I know, however, that most colleagues do not.
I think it is unreasonable to expect on board staff to carry with them the same full range of documents that you would expect in a ticket office, where they have computers, printers, files, cupboards, and plenty of storage and office facilities. Staff should have a general understanding of the relevant sections, but I do think it a bit unfair to be expected to carry the whole lot around - especially as the wording will, once it becomes common knowledge (see PFAS website linked to above), allow timewasters and generally awkward so and so's to cause no end of issues.
As regards restrictions, again we do not have the full range of facilities available. Whilst many simple tickets such as cheap day return etc are easy to find the details for on Avantix, trying to work out the complexities of the validity of a Super off peak return to London based on the limited and difficult to read text on Avantix Mobile is a nightmare - especially when many passengers ask for a ticket, and then (in my experience) when you try to explain the restrictions don't want to listen or say they know them anyway.
Now the latter point is no fault of the passenger, but I wish ATOC would think about what they are saying and try and fix something like Avantix Mobile (which, don't forget is used more and more on stations, gatelines, small station ticket offices etc) before implementing these changes. I'm sure Avantix Mobile is capable of being updated to make getting such information - especially routing information - much easier, but it needs someone to do it.
The wretched machine can't even tell you which route a ticket is valid for until you have printed it out. Based on the image below, please tell me what the different routes are for this particular journey? (Whilst I happen to know what they are, as it is a ticket I see often, if it is for a journey I am not sure about there is absolutely no way of knowing what the "Not via..." bit says until you actually sell the ticket.)