What is the "better / best " method to multi-boot different OSes natively WITHOUT VirtualBox(es) ?

[Ralf Mardorf]

PS:

Electric guitars tend to have grounded strings, to make the guitarist's
body a shield. This grounding might be provided by a guitar amp
connected to different mains, than a mixing console's grounded metal
case is connected to. It shouldn't matter, but it not that seldom does
matter and I'm assuming that amp, cables, guitar and mixing console
aren't broken. Somehow it seems to happen, that ground not that seldom
is fishy. This is one of the reasons that makes me overcritical.