I've been a technical author in my time, and also a programmer, so I can be sympathetic with both sides. It can be very difficult for a lone developer who's been immersed in their work to get the detached viewpoint needed for a good manual - or indeed a good user interface, which is where the problem usually starts.
I too have been a technical author, and the problem I always had was the demoralising knowledge that NOBODY EVER READS THE MANUAL! I remain convinced that if I had inserted "Contact us for a free Mars bar*" somewhere other than the front page, the company would never have needed to hand over a single Mars bar. So it warms my little heart to have people keen to find and read manuals! Anyway, </grumble>, lest I derail the conversation.
*Note for those not in a country where Mars bars are unknown, they are a confection or candy, sold in single-serving wrappers, consisting of a chocolate-type coating over a stick of nougat and caramel. They make a pretty good chocolate toffee sauce if melted in a microwave.