I ran my AKG 460s from '94 until around 2002 using the stock mic clips that come with them, and rarely had issues with hearing bumps, and I know my stand was whacked many times at GD, Phish, and WSP shows in the early '90s where I seldom heard anything on playback that was louder than the sound pressure of the show enough to make it audible. Similar to the OP's recent experience.
However, I started taping more in clubs in 2002, and I definately noticed the vibration caused bass resonance that was picked up through the stand coupling to the floor that you don't get as much when taping in large venues off big line array PAs. For this reason, I got a pair of the A53M Shure donuts and instantly noticed the bass was audibly tighter and cleaner, particularly when taping in boomy clubs.
Shockmounts are clearly beneficial for reducing both bass resonance and bumps in lower sound pressure situations such as on stage for unamplified acoustic instruments, which explains their wide use in professional settings. So, are shockmounts a "taping urban legend"? I guess it depends on your application.