I'm not sure how this is idiocy... how do you think electronic techs serviced televisions and monitors? You HAVE to run them open to even probe for correct voltages or take O-scope readings.

Just use reasonable care to avoid touching live circuitry and you should be okay. I have repaired several dozens of CRT TVs and monitors back in the day. The 30k volts from the flyback output can potentially kill you, but it's low current so most likely you'd just get a very uncomfortable jolt like being hit by a stun gun, although I don't speak from experience because this is one voltage I've never accidentally touched. BTW, the B&W tube in a classic Mac probably only gets closer to 12-15kV.

Although I would have to admit that I've had my share of accidents. There have been times that I've forgotten to check large electrolytic caps in the primary circuit of TVs only to discover they still retained a pretty sizable charge. I've also accidentally brushed against live heatsinks in monitors and power supplies. I've been lucky every time that all I've gotten every time is a weird buzzing/tingling sensation running up my arm.