I agree with you completely Superflux!
Many, many moons ago I was working for GD @ Electric boat in "Rotten" Groton, Connecticut as a shipyard welder... Back in the day, in order to become a welder/mechanic 3rd class, we had to qualify welding with a mirror w/magnet assembly and it was bend tested after passing VT... If you passed both, you were qualified but, the certification was EB's and you couldn't take it with you if you decided leave...
I remember that we had to get referred to the South yard welding school for a 2 week "vacation" from the Boats and without them knowing I was already qualified when I was in the service before going to work @ EB so, to me it was a vacation as were most of the other "vacations" I had when qualifying for this or that...
I mirror welded with 2 mirrors many times in many of the boats whether they be LA attack, Trident/Ohio boomers as a "hanger banger" and in some very unique locations and situations and repairing too many bad welds regardless of their location... Without the luxury of moving anything that was obstructing access or my view to the weld deposit or repair location... On a handful of occasions I welded with 3 mirrors and whether it was 1 or 3 mirrors, I always had an apprentice that would connect or disconnect my stinger lead to the welding cable I used that was strung into the boat from outside where the 8 or 12 packs (welding power sources) were located...
We later came up with an on off switch to power on & off the stinger (We used twist lock electrode holders) in order to position the electrodes properly just before ignition and to power off so that we could safely remove the "spent" stubs without leaving some nasty
arc strikes that would ruin any job... I also came up with a rig that was an electrode holder attached by a clamping mechanism to a moveable elbow and telescopic arms for jobs that were too inaccessible and could not be reached with a broom handle alone...
It has been claimed that the conversion to modular new shipyard construction has virtually eliminated the need for "mirror" welding yet every now and then I'll see an advert for a mirror welder... Now that may be true about new construction but, repairs will always be needed after extended operations and they're not going to move stuff in order to access whatever needs to be repair welded... So it's a good bet that mirror welders are still in high demand @ the various shipyards in the USA as well as many power plants also.
Many, many times the use of my right hand was necessary to get the job done and if anyone refused to do so, they would lose their whatever class welder/mechanic status from that day on and become reclassified as a welder/apprentice until they could prove otherwise by welding everything, everywhere with which ever hand the was necessary to in order to complete the job ticket...
Because I was a leftie/southpaw, I was very much in high demands to perform repairs on the various boats so I was designated as a "rover" and I was well taken care of by the many supervisors I worked with especially after work when I caught up with them in one of the 2 bars that were next to the main gate with many complimentary rounds by them for getting the job done where many before me failed to do so but at least gave it their best shot in attempting to complete a critical repair weld or any number of pipe hangers that had to signed off by a certain date in order to stay on time with their schedules... Those days are long gone and I know that I could NOT do that type of work even if I was healthy @ my age but it was fun while it lasted!
Respectfully,
Henry