I have a pretty standard timing belt setup; two gears, a water pump, and a
tensioner/idler.  I was talking to someone and timing belts came up.  I
mentioned that after replacing my timing belt, if I stood near the belt and had
someone hit the gas, I could hear a faint "whorling" from under the timing
cover that I didn't recognize from before.  I have an idea what a too-tight
timing belt sounds like, and thought that I may have gotten it on a little
tight, but nothing too serious because of the low volume of the noise.  Well,
this fellow disagreed and said that any noise coming from that area was the
bearings under stress, and thus a timing belt that is on even a little too
tight is going to shorten the life of the camshaft and water pump bearings as
well as the timing belt.

Is he right?  Are the bearings the source of the "whorling" noise?

Does any noise at all from the timing belt area imply a shortened belt life?
What about bearings?

Is the (presumed) shortened bearing life due to heat from excess friction, or
due to the shafts spinning slightly out of round from the belt pulling on them?

To be more precise with setting the belt tension, is it safe, as this fellow
says, to apply tension to the belt with the engine running and idling?  That
way the noise would be immediately detectable.  I did the best I could
measuring the belt deflection with the engine off.  Honestly though, I was
guessing at the force to check the belt deflection since I knew of no way to
precisely create the force quoted in the shop manual.  I just pressed on a
floor scale to obtain the number and then tried to press exactly that hard on
the belt.

When tensioning it my overall strategy was to try to get it to the point where
the tension was minimized but where there was no back and forth play in the
belt as I turned the crank, and I believe I succeeded there.

Or maybe new belts make noise as they break in.  I've never done one on my car
before so I wouldn't know.  It is a Gates belt.  I do have a new tensioner.