I have been playing with Steem mining. I got the software running, but I'm really not sure how much progress it's making. After running overnight it's still showing blocks estimated to take around 900 minutes (15 hours), which is no better than when it started.
It's showing some with 450 minutes, but I'm not sure any actually get completed. I set it to run 2 threads so my quad core CPU would still allow me to use the PC. I'd expect it to work on a couple of blocks to completion, but maybe it's doing something else. I really don't fully understand how the mining process works.
In any case, I am unlikely to actually profit from this. The mining queue still shows two people getting almost all the blocks. There seems to be some debate about whether they have managed to produce a GPU app or maybe they just have access to lots of PCs. Steem mining was intended to be CPU based to make it more accessible. I assume that's by making it memory intensive.
So, all I may be producing is heat and a higher electricity bill. I wasn't expecting to get rich from this, but I can't stand waste, so I will shut it down for now.
Let me know if you find any good explanations of how the mining works.