Yeah, I always figured it was something like that. I included a similar -- though nowhere near as detailed and precise -- explanation for it in a couple of my Trek novels. Nice to have it confirmed by an expert. (Actually I got the idea from Mythbusters' episode about whether lightning strikes could electrocute you on the phone or in the shower. They can.)
Look at it this way, we are talking about the equal of MILLIONS of amps of electricity... plasma surges and other exotic powers and fluxes here. Normal daily operation no one gets zorked, zapped, zotted or voom'd (requires 4,000 volts). It takes extraordinary situations to cause stuff to explode or shock people.
Now if in the course of daily operation people were getting face-fulls of console or power-surges to the crotch THEN I'd be more worried.
The fact is that these (imaginary) devices keep the internal explosions to a minimum... considering the power levels we're talking about.