The client asked for my opinion of how I would figure out what the UX should be like for their users (i.e. the bankers and their clients), and I said I would talk to them to find out. She blinked and asked me, don’t you use personas? At which point I said, “huh, why would I do that when there are actual users serving the clients every day who know best what tools and functions they need to have in the app instead of me the outside consultant trying to pretend to be them and figuring it out…”
I’ve sat in full UX workshops before to brainstorm app features using personas and I think it’s great for the initial fleshing out for new product ideas with, as you say, an incredibly large number of potential B2C users.
But I find it ludicrous for an outside IT vendor to try and design a bespoke enterprise app or software with a limited and highly select group of internal stakeholders and their clients by pretending to be them…