It was in William Stephenson's book "A Man Called Intrepid" that I read a bit about that, and the repercussions that the local population was forced to endure. Serious times, drastic measures, but I always pictured the scene playing out like in a cheesy 50's B-gangster flick: assassin sneaks around corner of building in broad daylight, dramatic music playingllltosses bomb while standing (practically invisible to all around him) in the middle of the street, about five feet from his victim. Music peaks. Big cloudy poof, ill-timed bang, door to car (undamaged) is seen flying open as cloud of fake smoke unfortunately parts at an inopportune time. Heydritch staggers from car with really jerky motions, reaches for luger in belt holster (which is buttoned closed), fires a few blanks with tell-tale puffs of smoke gracefully wafting from end of barrel (holser is still buttoned closed), grimaces in exaggerated pain whilst clutching chest of immaculate uniform (no holes/damage of any kind), falls to street. Cut to very determined-looking would-be assassin running down street as pedestrians continue doing what producer told them to do five minutes ago. Cut back to Heydritch, lying in street (different position, as he had to get a latte during the break and couldn't remember where he was laying) as medics in cheap labcoats and stethoscopes scurry over to where he lies, trying to look authoritative and medical. Give him two aspirin, have him call them in the morning.
That's just how the voices in my head see it happening.