Why not Implement Improvements from some Altcoins into Bitcoin?

[Bill Bisco]

Altcoins promise an array of varying features that try to entice people to use the altcurrency instead of or in addition to Bitcoin.

My question is:  Why not implement most of the praised features from altcoins into bitcoins as they are developed?

[gmaxwell]

Most altcoins change almost nothing at all. What they do change is sometimes outright bad, ... but mostly just a twiddling of different tradeoffs and not actual improvements.

E.g. some change to continuous difficulty adjustment, but that greatly decreases the cost for an attacker to mine out a low difficulty fork to trick an isolated node.

Sometimes the changes are bad enough that they make the coins so insecure that they actually are successfully attacked.

[amincd]

I think the Bitcoin community should seriously consider changing the block time. I'm not saying it's the right choice: maybe a longer block time is needed for a global cryptocurrency with millions of nodes, but it's worth weighing the pros and cons.

Bitcoin should be willing to adapt without sacrificing its 'core principles', which are decentralized proof-of-work based consensus arrival, a 21 million coin limit, and e-cash qualities.

[nomailing]

I think the Bitcoin community should seriously consider changing the block time. I'm not saying it's the right choice: maybe a longer block time is needed for a global cryptocurrency with millions of nodes, but it's worth weighing the pros and cons.

Bitcoin should be willing to adapt without sacrificing its 'core principles', which are decentralized proof-of-work based consensus arrival, a 21 million coin limit, and e-cash qualities.

Yes.
We should also talk about the pros and cons of adding scrypt as a second proof-of-work.
We should also talk about the pros and cons of adding proof-of-stake.

We should really be ready to fight against centralization of bitcoin miners. Just keep in mind how the ASICminer company is building up their share and how dangenous this is if you consider attack scenarios like selfish mining.

[amincd]

It might be nice to have a separate forum section for discussions on protocol changes. All of these deserve discussion and consideration. I don't think the BTC protocol should be frozen in time at what Nakamoto put in place in 2009. Ruling out tweaks would prevent Bitcoin from fulfilling its full potential, and provide an easy competitive advantage to forks.

[Bill Bisco]

I totally agree with the above.  This wait time for confirmations is killing me.  I should be able to confirm a transaction quickly and be able to move on.  How can we expect people to use bitcoins at the cash register if it's like this?

[gmaxwell]

I totally agree with the above.  This wait time for confirmations is killing me.

There is nothing in the protocol that can be changed to effect that substantially. Uncertainty and variability in time to irreversibility is inherent in an anonymous consensus system. Twiddling around parameters may change the distribution of values somewhat, but there will always be long confirmation times intermittently.

How can we expect people to use bitcoins at the cash register if it's like this?

The same way they use credit cards— which are not irreversible for months, Bitcoin is irreversible very fast compared to credit cards.... or through any of several different ways to achieve instant irreversibility with some tradeoffs externally to the network.