Actusreus,
I took the pulley, brass collar off the motor, and cleaned everything up, after a year there was a little bit of dirt mixed in around the stationary area and on the collar. This is the primary advantage of dis-assembly versus using the syringe method, the ability to clean the area. I used a tooth pick to oil the top part of the Armature (rotor), adding about 2 - 3 drops. Then I also oiled the stationary area, the bushing, and the Armature shaft. I originally put everything back together as described in my email to Mike and left it like that for about 2 - 3 weeks. I then corresponded with Mike, and received the method which I posted. Essentially he is saying that the collar is needed to ensure the symmetrical position of the Armature within the stator. That did make sense to me, since as I did mention, the collar is recessed to fit the stationary area on top of the motor. Lifting up the shaft, lifts up the armature, which re-positions the armature in the stator. It also in turn, puts a little bit of pressure, from gravity, against the collar as it fits like a glove into the stationary part of the motor. I surmise, based on MIke's remarks, that it is important to have that little bit of gravity pressure against the collar. This also keeps the armature centered when you have the additional sideways pressure from the belt.
Ultimately I re-positioned the collar, exactly as Mike instructed in the email. I put the shaft all the way up, then tightened the collar, so there was no play. I then barely loosened the collar and allowed the shaft to fall a very, very small amount. So right now there is an almost imperceivable amount of up and down motion on the shaft. That is how I currently have my motor configured. If I make any more changes, it would be to give it a little more play, but right now I will leave it as is. Also, since I know the collar is rubbing against the stationary area, I will be very diligent about keeping that area oiled up.
As far as "noise" coming from the motor. I believe the primary source of noise is coming from the collar rubbing against the stationary area, however, I will say, that with Mike's method it is very uniform, whether the belt is on or off of the pulley.