...., you will have shocked yourself a dozen times by touching live surfaces if they haven't shorted to something else first.
....
That is pure fantasy-horror, fear mongering, meant to scare people. I've worked on dozens of PSU's and never shocked myself once...if you have let us know with specifics. Fixing a PSU in a way that works reliably in your system may require some pretty good tech skills, but just poking around inside a PSU safely isn't high skilled tech work. You can do so with simple precautions...and most of the most important ones were taken already for you by the designers.
I've discharged 10,000mF caps in the HV power supply of UHF transmitters (800VDC plate voltage) and all I ever got was a pop...never anything as horrendous as you relate. There's just not much energy stored in a capacitor, even big ones. While there are electrocution hazards in such equipment, that isn't the hazard from accidental discharging a capacitor... it was jerking your hand/arm out of the equipment and cutting yourself.
If the cap's not got an exposed lead, e.g., it's mounted flush to a PWB, then all the better as it's protected against accidental touching. Just short everything you can get to to ground if you're concerned.
OP said he's aware of the hazards. That means to me he's not likely going to go fondling things inside with his fingers anyways.
But here's another reason this fear-mongering is more imaginary than real: IF there are sufficiently hazardous voltages inside the PSU after removal from primary mains, then there HAS to be the safety bleed-off resistor or circuit included in the design you refer to. It's standard design practice in modern electronics and probably a requirement for UL and other certifications. I'd be very surprised if it's not present in even the cheapest PSU on the market (it's cheap to do), but on the outside chance that's why short everything to ground (the case) that you can.
Also, a curious observation, I don't recall that any of my PSU have been labeled with required cautions about hazardous voltages being present when removed from power. How can they get away with that and still carry UL and other certifications?
The WORST hazard I'd admit to as a serious consideration is that while poking around someone's going to unwittingly break the PSU and leave it in a state it could damage/destroy the system, or worse create a fire hazard.