I agree with this.
There is on one hand architecture, and on the other usability. The end users shouldn't directly be involved with the architecture, but since they are going to use the thing, they should have a whole lot to say about how it should work. Not some guy who makes up some arbitrary user stories based on a few talks with end users (but those can be a base to start with).
In the (internal) project I'm working on, at first we had a non-programmer collect requests from the end users. He would come back with things like: user X wants a button here that does Y. Then I'd say, hmm OK, and what is he trying to solve/improve by having that extra button? What are the use cases? Then the guy would go back, and it would ping-pong a couple of times. In the end it was often more productive to go talk to that user directly.
There are caveats though.
End users often don't know what they want exactly, only that they have a certain frustration that they want fixed, and they will often propose what they think will solve it (very often a magic button). So you need to take the time to find out what it is they really need, and then see if there is a generic solution for it that fits in your architecture and process flow, that might be useful for more than one user.
They also often have a very narrow view of the problem, so you have to inform them what the impact is of their new feature on other users or other parts of the software. Quite often they didn't think it through and even left big holes in their own use cases. They often request features they need NOW, so you always have to weight the costs against the benefits.
Direct user interaction also helps setting realistic expectations. We can quickly guess if it will be a complex feature, explain why it is so complex, and why we probably won't be able to implement it. End users often expect the software to perform magic, using incomplete data to perform error free tasks. Things a human often cannot even do given all data and experience.
This all leads to less user frustration, and an overall more streamlined workflow.