This was a good read.

Let me lead with - I wouldn't use a silver dollar at McDonald's on the dollar menu because, even though the tender is intended to represent $1 USD, the melt value is much higher.

It's worth nothing, upvote bots may have some role in lack of pegging to $1 USD. By sending 1 SBD to a upvote bot, the return right now is approximately 1 SBD + $ 1 USD worth of SP under a stable value scenario (before curation's cut). The reality is of course, there is a likelihood of ending up with less SBD than sent to the bot originally, this is due to fluctuations in market price during the seven day period and timing of when upvote bot lands on the post. However, when I use these services, there is some reasonable expectation of receiving most of my SBD back under stable 7-day value, receiving some Steem, and the value of inherent post promotion.

Let me know if you agree or disagree, but it seems like pegging the USD value would be difficult when the upvote bot rate of return on 1 SBD is so attractive..
Nice job..
Kudos.. @knircky