Ok, I'm not sure that every politician can learn how in 60 seconds, but I was taught by Michael Waldbrenner about 20 years ago in less than 60 seconds, and have over the years taught 25+ Tekkies and Dive Instructors how to do it including finding the vein, and holding on it while listening to the blood flow and the bubbles swish past with around 60 seconds of instruction. Then testing that they can still do it 30 minutes later.
Admittedly hearing the exact Spencer grade cannot be easily learned, but what counts is really differentiating between :
Occasional bubble
Bubbles
Still countable bubbles
and Too many bubbles to count
Instead of riding your high horse, why don't you buy a cheap 8mhz doppler, and try it on yourself, your wife, and your son?
Now you will understand what you are hearing, how to find it and what it sounds like. When you finally hear bubbles after the day's diving on a dive boat, you will know what you are hearing, and then you'll have to differentiate betweel occasional, steady but countable and too fast to count.
Michael