It's actually quite easy to identify them by counting. If there are 394 vibes/minute, it's a 1-per vibe. If there are 788/minute, it's a 2-per vibe. Anything above that is a high-freq vibe.
Yes, that makes it all much clearer.
I hope that was a little sarcastic.
Think of it as "whop-whop-whop-whop-whop-whop-whop," vs. "whopwhopwhopwhopwhopwhop."
This does remind me of the time when I almost spazzed flying the TH-57. I felt a buzz in the right pedal and thought, "WTF?"
Then I realized I had my cell phone on vibrate in my leg pocket and had just gotten a call. This was about a month after an IUT had broken his back as a result of a T/R failure.