If you see $1 in profit per day per 1070 that's not guaranteed, considering if BTC dips 10% you could be negative. The closer we get to power costs the less leeway is available for BTC fluctuates.
I have been mining since 2013.In the autum of 2014 it was pretty bad. 4 years have passed and everything is much bigger now. More profit, but this might turn bad quickly. In a falling market it's important to have the fastest kernels with the lowest power consumption. NVIDIA sp-mod is pretty competetive here.
That's when I started, I wouldn't say more profit. Jan of '14 you were making $98 per 7970 and then everything crashed and burned.
It very much can, the volatility due to the size of the network and how much cryptos fluctuate doesn't leave nearly as much room for negotiation. As we've seen BTC can go up and down in a day as much as 20%, as networks come closer and closer to capacity (capacity represented by power cost at $.1kWh), those flucatuations will start eating into profit on a daily basis. The network can never truly reach capacity and be 'profitable' unless there is leeway in between. It used to be a $1 was pretty much guaranteed, now when you're talking about 100s of thousands of GPUs on one coin (such as Zcash or Ethereum) there isn't breathing room when we get closer to that $1.
Markets will continue to fluctuate regardless of what mining does, we can expect to see what happened in Jan as well as the climb that ended in Dec. As I mentioned the difference with Dec is the hashrate didn't grow to match that $19k BTC finally reached. Imagine what would have happened if hashrate had increased to that point as it's doing right now? When it dipped to $6k almost everyone would be negative except for farms that get insanely cheap electricity, such as China. This is something new miners and a lot of old miners don't really understand.
In a way we almost needed to reach below electricity costs this Jan to stop the explosive growth we're currently experiencing. Since we never got there we are now in a worse predicament where people can no longer tell where that bottom is (as the bottom is now rushing upwards with a increase in network hash to match the growth in BTC). Even though BTC is still increasing in value since the $6k, profits ($) are decreasing, but not as fast as BTC revenue is decreasing.