Inside the Cary Audio CAD-280SA V12R Tube Amplifier... And a major flaw to watch for!

My personal tube amp, a V12R F1 edition. I've already done some basic tweaks (doubled the B+ power supply capacitance, installed my preferred coupling caps, installed HiperFred diodes, replaced the ugly blue LEDs with inoffensive red ones) but in the course of doing so I found a shocking number of factory joints that were not soldered! In the end I found around 10 points that had the wire wrapped but not soldered. Amazingly it worked fine and had no indication this was the case. The joys of hand built point to point units.