Originally Posted by Trakhak

If you search for it, you can probably find a Bicycling! magazine article from the 1980s where Jim Blackburn reported the results of tests of all of the most common rack configurations (not including frame-mounted front racks, which were unknown at the time, at least in the U.S.): rear panniers, front panniers placed high, low-rider front panniers, handlebar bags, top-of-rack front and rear bags, etc.

He found that one of the worst combinations for bike stability was that which was most common back then: rear panniers plus front handlebar bag. That combination brought out the worst tendencies in the steel bikes that he tested---in particular, the awkward "wallowing" that discouraged pedaling while out of the saddle.

On that topic, I'm pretty sure all the test bikes were steel. Since then, Cannondale aluminum touring bikes have generally been praised by the comparatively few riders who have toured on those bikes, which ride well because the torsional rigidity of the frames mitigates or eliminates that wallowing problem. (It's noteworthy that while American touring riders still seem to prefer steel bikes, a significant proportion of the European touring bikes on the market have aluminum frames, usually combined with an aluminum fork.)

The best of the tested combinations was the use of front low-rider panniers alone, with as little weight as possible added elsewhere. The test riders found that weight in low-rider panniers actually improved the way the bikes rode.

I can attest to the benign effect of low-rider panniers. My shopping bike, a 1995 Cannondale H300 hybrid with flat bars and a pair of panniers on low-rider front racks, is effortless to steer at anything above slow walking speed. The only time I notice the weight up front is starting from a dead stop, and even then only for the first pedal stroke.

I don't know whether the low-rider pannier/rack combination improves or degrades no-hands riding. Why would I care? The hands-on handling is perfect, which is all that matters.