Thanks Nathen!

There were 11 accounts in the 1500+ author bucket pre voting-bot deductions, and 5 once voting bots were removed. Once you add in curation and benefactor rewards I'm pretty sure the user you're thinking of wasn't the top earner, even with the additional curation rewards from their alt account. If I were to add in the witness rewards, there would be some fair competition for the top spot.

The use of alt accounts is a good point. There's no concrete way to sum across the different accounts of a single user. I'm guessing a lot of the low earning accounts may belong to single users trying to farm which will upset the distribution somewhat.