These don't change the inflation cost at all.

I'm a fairly smart guy who has been trying for six months to understand this economic system. I keep failing. This post describes the importance of destroying SBD becuase that is debt in the system. Doesn't the amount of debt in any system contribute to its inflation in a practical sense? Conversions destroy SBD which lowers the overal debt but that doesn't impact inflation? Yeah, I'm still confused.

Has anyone written a steemit economics for dummies yet?

What OP is getting at in terms of 'attention economy' is people being willing to pay for promotion as an indicator that the attention of users is valuable. In the long run this form of payment could be a large inflow that more offsets the inflation expense of paying rewards and pulls value into the system, in exchange for the users' attention that the system is able to deliver (in turn by being fun, useful, and valuable to the users; though it is also possible in some models of an 'attention economy' that users are also paid directly).

The debt question is a different one, also important, but promotion could work just as well in terms of being part of an attention economy if it were STEEM being burned instead of SBD

@smooth, if I could get your perspective on this it would be a great help ..

I agree btw, STEEM not SBD, but what if it was made possible for STEEM to be put into the post's total rewards pool, directly, which would result in a more 'natural' form of promotion, given that it naturally increases the visibility of the post due to the reward itself and would naturally attract more interest. Then, the STEEM would be distributed to the curators with some coming back to the author, alternatively and better still, if someone decided to invest in the author's work/project by "tipping" it.

The author or investor would either be purchasing STEEM to do so, or it would come from their own balances, much of which would end up POWERED UP by either the author or the curators.

I must admit I do not understand the benefits or necessity of 'burning' either of the currencies, but this would certainly put some STEEM 'into play' as it were. Perhaps I am just demonstrating my ignorance here, but it seems it would have multiple benefits and potential uses.

Much appreciated sir!

That is somewhat like tipping, which has been discussed quite a bit. I think someday we will probably see some form of tipping on the platform, but I have no idea when nor what form it will take (and I could be wrong)