So for now I do not see bitcoin to break $6k levels at all, it is a psychological price level where miners do not allow you to sell, they buy as many as they can afford when the price goes below that to keep it higher.
Miners buying to support the price? Highly unlikely. I'm even of believe that they aren't really that worried about the price to drop because that forces less profitable miners to turn off their machines.
In that case it means the difficulty goes down which makes mining slightly more profitable for those who continue mining, and that slightly better profitability is enough to counter lower exchange rates.
I think it's more the overall trend and support levels that traders respect. The market has been taken over by bots and whatnot operating within a safe range they aren't willing to break.
regarding miners, people are usually looking for some sort of reason to speculate about the price and how it is going to change. in this case they are using mining, difficulty and cost as a reason for justifying the bottom at $6k and reason why it won't go any lower than that.
right or wrong of it rarely matters as it creates market incentive to react in certain way. for example the Mt Gox case was completely FUD since they weren't even selling on the market and their sell-off has been going on long before it became public or even drop started. but enough people believed it is the cause that THEY sold and caused the drop. in comparison enough people believe miners won't let the price go down that THEY will buy bitcoin and won't let it go down!
of course that is not always the only reason. there are a lot of reasons for every rise and fall.