BlackCoin had no premine, and also the analysis you cited doesn't claim that. Every initial distribution model of a PoS coin happened in a short time, in BlackCoin through a short PoW phase. People quickly use the term "instamining" which is actually a term for PoW coins with a ridiculous block halvening policy.

The current distribution of BlackCoin is better than in most alt coins. Regardless if you think that BlackCoin is a good investment or not, you will hardly find a second PoS coin code base that contributed so much to the cryptocurrency community. Several coins in the voting are BlackCoin forks btw.