This is a good point. Block reward is fixed, tx fees are not. Thus, someone can solve blocks at negative cost and bankrupt all other miners, since he can reduce his tx fee to 0.
This is a nonsense statement. It's impossible for any entity to bankrupt all other miners, no matter his transaction fees. Not only would any such miner have to aquire the capital investment in order to build his network to beyond 51%, an uphill battle considering the vast majority of the current running network (now or at any other time) is a sunk cost already paid for; he would also have to compete with the hobbyist miners who benefit from co-generation of waste heat.
I have a GPU based mining rig that I choose not to use, that I can use for space heating in my garage at will. No miner can bankrupt me.
Therefore your "law" is invalid.
That has nothing to do with my Law. That was what someone else posted, not me.
If you believe you can use your mining to convert electricity into heat, i hope you live in a very cold climate.
I don't, personally. Yet, for this exact reasoning, I have long ago predicted that Reykjavík, Iceland will likely become a mining hub due to the confluence of factors including a relatively low electric rate (due to geothermal resources), a high demand for space heating and a high degree of international Internet connectivity, along with other more minor factors. I also predict that asic mining chips will eventually be included into electric "heat trace" cabling intended to produce spot heating to protect public and private infrastructure from extreme cold. I've personally been involved in many such projects, and the cable currently in use, although really just a continuous resistor, is already very expensive. A co-mining method would simply represent an alternative income source to counterbalance the capital costs of such infrastructure. Oil and gas pipelines in the arctic require quite powerful heat cabling across their entire length. Imagne the hashrate of a strip of asic chips along a linier network and power line, with each chip placed one per foot along it's length AND circumference, in order to achieve a targeted watts per foot. In my own mild climate, the watts per foot range is 3-7 watts per liner foot for insullated pipes of less than 3" in diameter and 7 watts per square foot of insulated surface. I have not even seen a project that was les than 3 watts per square foot. Every public parking garage in the US built since 1985 (in regions that freeze in winter) has pressurized sprinkler systems required by code & insurance, and every linier foot of insulated pipe you might see when you look up has at least 3 watts per foot of heating cable that must energize whenever the local temp drops below 33 degrees (and usually much warmer due to insurance worries). What do you suspect woudl happen once Bitcoin is as big an economy as many of us believe it will be? Do you honestly think that Bitcoin wise engineers
will not incorporate spot heat co-mining in such infrastructure?