if i understand correctly, soldering points on the board is for the purpose of flashing the onboard TSOP. This is something that one might do to get a more compatible BIOS version onto their xbox. for example, if you find the bert is cheating on ernie evox dash stuff, apparently at this stage it only works with retail BIOS 4034. If you had an xbox with a different retail BIOS (you should be able to tell the BIOS version from the evox settings once you get the 007evox hack working on unmodded box), you could open the xbox, solder those points, then use evox to flash the 4034 BIOS onto the xbox TSOP. However, I imagine that some time in the near future Project Phoenix will have multibios support for their dash replacement hack. Personally, I'd rather wait for the multi-bios support rather than opening the xbox, but that's just me.
As far as xbox versions go, I haven't had this cleared up for me much either. As I have gathered, the 007AUF with evox hack technique should work on any version xbox. But I am uncertain as to whether any of the dash replacement tricks would work on all versions. Probably the same BIOS compatibility issue. Hopefully this will all be cleared up by software means very soon.
-nsn