It’s probably a sign of the times that every self respecting value investing blog has to have a post about bitcoin. And when you tell a random person that you invest the first question these days is if you own (or trade) bitcoins or not. So I guess “The Alpha Vulture” can’t stay behind, and share with the world what it thinks about bitcoin, whether you want to hear it or not. As the title of this post implies I’m skeptical about bitcoin, and most other software projects that are based on blockchain technology.
To explain why I’m skeptical I’ll first try to explain in the simplest possible way what the whole fuss is about because I suspect that part of the reason why people are so enthusiastic about the blockchain is the fact that they don’t really understand the technology. If you read an explanation about bitcoin you hear cool terms like distributed trust (which is actually cool) and stuff you probably don’t understand without a computer science background (like hash functions). These things are actually not that hard to explain, but not really necessary to understand the key idea behind the blockchain. What you basically do is, instead of trusting security to a single party that (hopefully) has a smartly designed system you substitute that by a large amount of computational power provided by multiple parties. There is a lot more to it than that, but that is just noise and implementation details.
The fact that you don’t rely on a single party is great! I’m not going to dispute that.
The fact that the security is provided by a large amount of computational power is bad.
Just a large amount of computational power would actually not be bad. Chips always get faster and more efficient. But it’s not just a large amount, it’s a relative large amount. The security only works because the amount of computational power required to “take control of the network” is simply too expensive for a malicious third party to acquire (even temporary). So if chips get 10 times faster the computational power required to keep the network secure simply increases with the same factor. If chips get 100 times more energy efficient, the amount of energy required to keep the network secure doesn’t drop at all.
Additionally, the amount of computational power required scales with the value of the transactions being done on the network. You need enough computational power to make it unattractive for an attacker to acquire even more computational power and take control of the network. How much computational power this exactly is, is quite an interesting theoretical question (I don’t know the answer). But for sure the amount is high. An attacker only needs a short moment to inflict huge and long-lasting damage on the network. They could for example double spend coins, hurting not only those who would receive them, but also causing a massive loss of trust in the system that would be longer lasting.
So why is this all so problematic? It’s simple: high computational power requirements translate into (relative) high transaction fees. And that’s a problem for a lot of the applications that have been proposed for the blockchain. Using bitcoin as a currency is the biggest obvious problem. Most banks for example process millions of transactions daily, and most of these transactions are almost free because running a nice secure sever that handles a million transaction a day isn’t a lot more expensive than one that handles just a few transactions.
If you use bitcoin to speculate on the value of bitcoin transaction costs of a few dollar aren’t very problematic. If you use bitcoin like some sort of virtual gold slash store of value it’s not a real problem. If you use bitcoin for money laundering or other black market transactions it also not a problem. But for the first two to work out I think you need bitcoin to become a broadly used medium for transactions, and just betting on there being a large black market is a questionable proposition as well in my mind. The current hype is mostly driven by speculation, and for most real-world applications high transaction fees are a very serious obstacle. There are probably some niches where it makes sense, but I think broad adaptation of blockchain technology would in most cases be a step backwards. And I’m only looking at the financial angle here, not even mentioning the environmental impact it would have…
Author has zero blockchain related exposure
 I’m using the blockchain and bitcoin sort of interchangeably in this post. I know it’s not the same.
 I doubt this is true. There is probably some complex relationship between both the cost of new chips, the energy requirement and perhaps even some other tangential factors.
 At least not a factor million more expensive. Scaling performance is still hard. It is also going to be hard for bitcoin.
 Average transaction fees are now already ~$4, and this is despite the fact that miners are currently also compensated by newly mined bitcoins. Currently miners get 12.5BTC for every block mined. With roughly 2,000 transactions per block and a current price BTC of ~$5500 one transaction actually costs almost $40.
 The fact that all transactions are publicly stored in the blockchain might be though…
 I used to own a couple of dozen bitcoins in 2011 or something like that back then when mining them on your own graphics card was still economical. Sold them between $20 and $30. Still better than buying two pizza’s for 10,000 BTC though.