Look at the pig farmer example I gave you. It's a good model to work with, good level of abstraction because you can actually build on it/tweak it to reflect reality in a more nuanced/exact way.
For instance, you can make it more accurate by allowing for the fact that you're not the only pig farmer, and many pig farmers will go out of business when halvening cometh & pig price is cut in half. You can plug in your own profit margins, model pork belly futures (mining contracts), etc, etc.
Yeah, I skipped the example altogether because it assumed equal farming efficiency and costs, which isn't really suitable for the ASIC analogy where you have much faster equipment and more energy efficiency.
And I can't see how I can tune it to make one farmer better at ...growing pigs, when these have a very predetermined type of growing. Cost efficiency, yes, this we can tune, saying one farmer needs X money to grow a pig and another needs X/2 money to grow a pig.
We can easily factor this in by assuming pig-raising costs are not the same for all farmers (which also happens to be the case IRL. Raising a pig in a NY penthouse is costlier than raising a pig @ a Chinese Pig Factory.). So let's say it costs some pig farmers only $5 to raise a pig now, while $10 for others. How does this break my model? Sure, the $5 farmers will remain profitable after the halvening, but ...so what?
We can adjust the costs. But how can we adjust performance? The only way I can think of, is, let's say farmer A gives hormones or a special diet so that his pigs get twice as fat in 6 months, compared to those of farmer B.
Because that's the issue here. Lower nm chips are typically more energy efficient for the same number of transistors, but changes in circuit architecture can also increase performance. So you have 2 elements to count.
It's not like you have 100 ghashes from one chip and 100 ghashes from another but the second just so happens to burn less energy. You have more ghashes as well. This means that the equipment that ultimately shuts down represents a smaller hashrate.
>But how can we adjust performance?
Bigger pig farm = better performance. No need for pig steroids (faster chips), just raise more pigs (more miners, bigger farm) -> will have more pigs to sell. Easy peasy
Remember, the slaughterhouse doesn't care how quickly you fattened your pigs; all it cares about is how many pigs you got to sell.
>the equipment that ultimately shuts down represents a smaller hashrate.
Doesn't follow at all. Let's say the majority of mining gear today is mining 1 BTC @ cost of .7 BTC.
When teh Halvening cometh, that majority will [likely] shut down*
The gold mining/dredge bit doesn't work too well for Bitcoin. Haven't been following mining lately, but rule of the thumb was breake even in ~3 mo -- if you don't, you ain't going to. Because while your dredge was dredging, other, more efficient dredges got to dredging, right where your dredge dredges (you don't stake a claim in Bitcoin, everyone mines for the same coins), requiring you to either upgrade your dredge or GTF out of the dredging business.
I'm talking about mega-dredges which were mainly used for inland mining:
https://www.youtube.com/watch?v=7OyEvwCpuuQ& Again, what is different? The gold miner without a staked claim (exclusive rights to the spot he mines), is subject to poor godless savages swarming in & mining the shit out of his spot. That is the case for Bitcoin -- everyone is competing for the same *cough* "digital gold"
*of course, this is not necessarily the case; we're not factoring in if *other miners have shut down (thus lowering difficulty -> making our shit gear profitable again)*. There's a prisoner's dilemma/Mexican standoff thingy that will happen when Halvening cometh...