Or, maybe it could mean that both those particular RL rugose parents have RL foliage Ff, where Ff + Ff results in a quarter of the plants being ff = PL. (A quarter each of FF, Ff, fF, ff being the combinations possible, but wherever F occurs it dominates thus giving three quarters RL plants).
If this scenario is true, it will be very interesting in the dwarf crosses that have one parent as PL (eg. Green Giant and Stump of the World).
Any germination on Sleepy yet J?
PP