Hopefully, I have the answer to my problem. As last night was the bearing, brake, & drivetrain night of my bike repair class, I took above bike with me. Yes, the chain was just short of 1%, so it now has a Sachs. The cables were fine, and the adjustment seemed OK. It turned out to be a very subtle rotational misalignment of the front derailleur. The classes (Park Tool School) are great. There were only 6 signed up. My benchmate had to repack his front wheel bearings, someone else needed a new bottom bracket, and several cables and brake shoes got replaced. There were 2 mechanics helping everyone through their basic adjustments and repairing the problems they discovered. They also offered to help if things didn't seem right in the next week. The manual is also very good. I give it a 4/5 star rating, and I will certainly make a stop at that shop the next time I shop for bikes or supplies, even if it is 30 miles from me.