When was the last time you saw someone buy a .com.au with "y" instead of an "s" at a premium over reg fee?
It is the kind of name someone might register if they are stuck.
I don't like to assume things but can I ask, were you around when all the premium .com's were available to register?
If I was old enough back in 1995 era I would have registered every single C.com, CC.com and CCC.com I could. Unfortunately I was only 3 years old at the time.
I understand having a negative view and skepticism regarding the value of some domain names is healthy, but when it prevents you from pulling the trigger on a sale, I don't think it is healthy. Were you like this back in the 90's when all these premium LLL.com's were available?
Sometimes I think it pays to just take the risk. As long as your wins outnumber your losses you are doing fine in this industry.
And I do think owning any dictionary name, anything related to Finance and anything related to product names (as long as they aren't trademarked) are good buys in my humble opinion. Also any CCC.com and shorter is worth it.
Its a big world out there, and there are only so many names to share around. Internet usage is growing exponentially worldwide. Companies and small businesses are realising that they have to be online, and also the importance of brand names.