SD or STEEM Dollars protect you from STEEM hyperinflation silly.
Not really. That is a gimmick in the design attempting to fool you.
The SP are debased at 10%, but the main tokens at 100%. But the problem is the SP may also fall in exchange value due to the 100% debasement of the main tokens.
You can't have everyone move to SP and still debase what is left at 100% and not also effectively debase the SP at 100%. Mathematically impossible.
The mere fact that STEEM is 100% inflationary dosn't mean that it will be debased at 100% or at any rate at all, demand is key and with much less than 10% in liquid STEEM demand will always be high, right now for example demand is out of the charts and not only SP but also STEEM is gaining tremendous value(don't know for how long) instead of being debased.