I am more sensitive to the issue of people doing things with good intentions but cause harm to others or their property, I personally lost 90% of my belongings, "worldly possesions", to some one elses negligence that caused a fire. And did not receive satisfaction from an insurance company. So the issue of telling someone it is OK to plug a welder in an outlet, when the person you are advising may not know better, that may be undersized is wreckless. And it raises the hair on my neck, to hear someone give advice that may cause someone else ALOT of grief.
Indeed most enthusiasts are careful about the work they do, but plugging a welder into a circuit that is too small will cause damage, and will eventually lead to some point in the circuit failing. The failure may just melt a part to where it won't conduct, or it may start a fire. Hence my advice to hire a professional, or in the case of a rental, secure permission from the landlord to get professional installation.