Great topic and great answers. As you mentioned guys, the 10 minutes isn't a constant, and sometimes we only see 2 blocks in 1 hour, but other times we see 8 blocks or more in 1 hour. So, in the long run it's 10 min.

I have a question about this topic, so, better post it here than start a new topic.

If we turn off all the miners and only leave 1 pc with cpuminer running will the 10 minutes block stay, or since the complexity is a lot bigger than the mining power the blocks will have a huge delay?