It's completely safe, UNTIL YOU DISCONNECT YOUR INTERCONNECTS. The floating component may then kill you, if everything goes wrong a la Murphy's Law.
The ideal is for every component to have a ground-lift switch, which keeps the case grounded while allowing the circuitry to float. This is much easier to do when the component is being designed, rather than after the fact.
The ideal is for every component to have a ground-lift switch, which keeps the case grounded while allowing the circuitry to float. This is much easier to do when the component is being designed, rather than after the fact.