RE:RE:RE:Help me dive into this one...That's about the jist of it ... their main source of income is the dividends paid by their holdings in the fund. They do also write covered calls according to "some secret formula" but as far as I am concerned the premiums on those calls are a very small part of their total income. And of course they run the risk of having their shares called away if the holder can make a profit, which in turn limits their capital gains if that happens.
I don't really have an answer for you and I never cared to send the time or effort. You would have to go through their Annual (or quarterly) financial statements when released to track all their sources of income -- way too complex for my small head.
Lastly, they do "actively" manage the fund, so perhaps they make some shrewd sales and purchases to capture capital gains?