What did you think about what I gather is Sedleys major point, that this is targeted at the cyreniacs and is meant to emphasize the point that virtue brings pleasure as it is engaged in and is not necessarily painful (as the cyreniacs argued)?
To make sense of this I think we have to consider that the Epicureans we're using a more flexible / relativistic definition of "virtue.". (And if that is so then this ends up being good support for the argument that the virtue of the Epicureans is different from the absolute virtue of the other Greeks.)