Oh, yeah!
Amp clamp plus an oscilloscope, you can see the amperage draw of
each armature bar, and compare it to the others. In a perfect world, each "hump" would be identical to the others. In fact, they're as individual as fingerprints--exactly the same at first glance, completely different if you look closer.
The Eagle-Eyed will notice that the oscilloscope pattern repeats after a certain number of "humps", the ninth or the thirteenth hump, for example, may look remarkably like the first. The pattern's repetition is telling you the armature has eight or twelve bars.
A 'scope can be employed to discover the time it takes for the pattern to repeat. Let us say, for example, that the time difference between the peak of the first hump and the peak of it's repeat (eight or twelve or whatever number of humps later) is 10 milliseconds. Simple mathematics (60,000 milliseconds in a second, divided by 10 milliseconds for all the bars to go 'round once, equals 6000 pump motor RPM.
Given some experience ('cause, as Ken K said,
these specs aren't published) you can figure out if the pump is drawing too much or too little power, has a bad bar (or three) in the armature, and what the armature speed is, compared to other similar pumps you've tested.
God bless the amp-clamp and the 'Scope.
Remember, AMPERAGE (Current) can be tested anywhere in the circuit (as long as the circuit doesn't branch to other loads) but the voltage must be tested as close to the load as practical.
If you plug in your amp-clamp to a certain fuse location, you must determine how many loads are powered by that circuit, and disable all the loads except the one you really want to test.
If you check voltage near or at the battery or alternator, you'll miss the voltage drop further down the circuit. Fuel pump testing can't be done "at the pump" since the pump motor is buried in the nasty old gas tank--but you should be able to get within a couple feet of the tank connector, which is (usually) good enough. When the pump is removed from the tank, you'd inspect the rest of the "hidden" wire harness looking for crap like this:
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The new replacement wire, compared to the swollen and corroded original in-tank wire.