The manual is correct, but to add… Bleeding current off of individual cells, through the balance taps, is how the current is controlled for each cell. If the imbalance is great enough, then the overall charge current will be reduced (in the extreme the charger might shut down). A charger with a higher balancing current capability can deal with a larger out of balance issue with out reducing the main current, and thus avoid increasing charge time.

The example of cells coming into balance when charging does not necessarily mean the charger is balancing. It could just be the cells returning to a previously balanced charged state. Think about it, if one has a balanced and charged lipo, assume the cells are different capacity, when discharged they will end up at different charge states-voltages, out of balance. But since the same amount of current was drained from them, they tend to rebalance all on their own while charging. Note balancing is important as cells change over time (which they will).

Note for this reason it is generally a mistake to balance a discharged lipo. Best to balance at the end while charging. All balancing a discharged out of balance lipo does is cause more balancing while charging (and risks over discharge), not good.

In practice some different brands of chargers apply balancing differently. The PowerLab 8 charger for example can even be adjusted/configured for when balancing occurs as I understand it. (And has king of the hill balancing power, 1 amp I believe)

Hope this helps some, can be tricky to explain well.