Why does lowering interest rates transfer incomes from households to corporations?
A student of mine came up with a very plausible explanation for this statement. I think he's almost certainly on the right lines.


Low interest rates encourage consumption spending and discourage saving. (They might also encourage people to take out loans to fund consumption spending.) 
Consumption spending transfers money from households (who are buying goods/services) to corporations (from whom they're buying).
These corporations are assumed to save at a higher rate than households (see the quote in the question), so increased corporate savings more than offset the decrease in household savings.


It's obvious once you think about it!