I also have the same doubts that you have and I may even have more things to ask, unfortunately I can not find the answers. :(
Something I do not understand, when I started in Steemit more than a year ago the Steem was practically worthless... but the value of the votes of the dolphins and whales were much higher and now that many have more SP than a year ago they vote nothing, why? Can not do anything so that a person with thousands of SP can have a considerable vote like a year ago that even the Steem was not worth anything?
The programmers can not do anything about it?
one year ago Steem was way more worth than now.
Sorry, I was wrong... I was referring to the months before July when I started in Steemit that the coin was lower than right now.