RE. rinsing experiment: I've also found that rinse results are highly sensitive to the amount of detergent used. Excess detergent rapidly takes more time & effort & water to rinse out. There does not appear to be an obvious relationship between quantity of clothes, water, and detergent from one machine to the next, so a combination that produces good cleaning in one case without need of excessive rinses, may produce less good cleaning in another case or need more time/effort/water to rinse out in another case.
Re. water movement & agitation: If Mr.X's point is correct, and I believe it is, then it should be possible to get perfectly good washing results in a TL when using the gentle cycle. That is, the gentle cycle moves the water but doesn't move the clothes as much, so it should work as well as the normal or strong cycle, except in cases where some rubbing action is useful for example to get mud or cement or paint out of a shirt or pair of pants. In my experience, this has turned out to be true, and so I use the gentle cycle on TLs with perfectly good results, and my clothes last longer than they should by any reasonable measure. In fact I'm still wearing shirts that are about 10 years old but still look darn close to new aside from a certain amount of fading (i.e. the fabric itself does not show mechanical wear as one might expect from an agitator).