Then I understand. It fits your concept of pragmatism, while not mine nor Peter's, and it ticks off Martin Bähr's ideas of freedom. :-)
All that said, and without myself having dived into technicalities in a FishEye installation, I'm sure people would use the system if you brought it online somewhere and it wasn't required to run off the not-quite-state-of-the-art pike site. (Subversion has good APIs that make most things nonnecessary to run on the repository machine, so I'm assuming it at least possible. Though if it were, we would probably not have this thread in the first place.)
The reasoning to use any tool short of perfection is that it scratches some itch better than not using a tool at all, and those imperfections are addressable with sa[nf]e licenses.
Trac would have been great and already set up here, had it been comfy in a solaris locale or had we had operations linux based. FishEye may be neat if somebody sets it up somewhere and it just solves issues as well. We're no worse meritocracy than any other hacking camp, so "not invented here" never matters to "not maintained here" software. What qualifies as comfy rarely changes with arguments, though, so trying to convince any voice in the thread to embrace FishEye is probably moot.