The problem with the soundbite summary is that the analysis presented is incomplete. On the one side, 10% of customers might have noticed the drop in quality,

The problem with the soundbite summary is that the analysis presented is incomplete. On the one side, 10% of customers might have noticed the drop in quality, but we have no idea how many of them would actually go somewhere else to get their coffee. On the other, while 100% would notice the higher price, we again don't know what the demand curve looks like so we don't know how many sales they would lose.