I would bet my bottom dollar that the issue of hot plugging a sampling head
was discussed by its designers and would have been documented as a
no-no (or blocked by some mechanism) if there was chance of failure.
Still, one may think of hot plugging as a "bad idea", much like::
- playing with elemental mercury as a kid
- sanding lead based paint
- swimming right after eating
- waiting over 5K miles to change your oil
- "floating" a scope
- ripping up your asbestos laced flooring
- looking into a laser with your good eye
- putting down your beer, and saying "here,... watch this..."