Bentley wrong on alternator diagnosis???

[PBKScirocco at netscape.net (Phil Kerschner)]

I suspect my 90A alternator is going south.  So I took a look at the 
multimeter test located at section/page 13-11 "Testing Alternator and 
Regulator".  The test is run at 3K RPM and battery voltage checked first 
without and then with electrical loads (lights & fan).

It states "a reading that is the same as the first (without load) most 
likely indicates a faulty regulator.  A reading that is lower most 
likely indicates a faulty alternator."

Is it just me or does this seems backwards?  I would assume if the 
voltage dips up and down with loads applied/cancelled, then it would be 
the regulator??

For example, when I turn on the headlights at some point the voltmeter 
gauge reading will dip down below 12v, sometimes as low as 11.2v   So 
over the weekend I cleaned all my grounds and checked the regulator 
(brushes nice and long).  I picked up about .5v - .7v that way but it 
still is below 12.5v when charging.  When I apply turn signals the 
voltmeter gauge dips up and down  quite furiously.  I don't recall this 
happening previously.

So I am concerned as to whether it's the regulator or alternator.

-Phil