Unbricking HTC Desire HD - really need some help here!
To add, after a little thought I think the lack of a cache directory may have been my problem all along. I formatted this ext2 and this may have solved the problem. Therefore a damaged cache directory might have been the root cause of this problem.

after formatting the cache and running /sbin/recovery it went straight into Clockwork (it was a big surprise) .. I went to HBOOT and RUU'ed a new ROM immediately (unfortunately in my excitement and due to a mislabel by the uploader) it turned out to be a Telus one... which is giving me problems.. but heck.. simple ones.

The moral here is don't give up. Nearly everybody said this was a bricked phone. But, I think, if you have HBOOT/fastboot or (most probably need rooted) ADB access you can do many things to get things going - I learned a lot ))))