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Comment by azylman | Hacker News Reader

It depends what your success criteria is. It's true, you've successfully increased the throughput of the transit network, but you haven't done anything to improve transit times - you just have more people stuck in traffic now. There are other ways you could have spent that same amount of money (public transit) that both increase the throughput of the network _and_ improve transit times.

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But those extra people are choosing to be there so there must be some benefit.

> But those extra people are choosing to be there so there must be some benefit.

As long as your roads are saturated, they have less throughput, not more. It is kind of like a clog in your toilet: more things are there in your pipes, but not much is getting through.

A clogged toilet isn't flowing. More like dumping a 5-gal bucket into a sink . The drain is running at full capacity but any one drop may take a long time to actually clear the sink. The 5-gal bucket is peak demand. Total time to sink clear is how long rush "hour" lasts.

Fluid analogies are crappy because fluids flow more when you add pressure and traffic doesn't.

> because fluids flow more when you add pressure and traffic doesn't.

Well, traffic can flow when pressure is added, just not in a way that is very safe.

If your city sewer is clogged, so you widen it, then more people install toilets in their houses and bring the sewer back to capacity, I think that's still a win.

They're choosing to be there now, precisely like they were choosing to not be there before you changed the roads. Other people are also choosing to not be there, and instead choosing to live in the woods in northern Canada. I'm not sure how this mode of argument is really demonstrating anything. It seems like you just considering literally any state of affairs other than active physical coercion to be a good state of affairs.

Not if you build enough roads. This argument just does not hold up. There was less time wasted stuck in traffic in the past. Go with tunnels underground so as not the create the large problems with having surface roads. If your idea theory is right, why don't we just stop maintaining all roads, shut them down, and save a lot of money, if new roads are useless.

In some cases it might be theoretically possible to just outspend the problem. But in most cases the roads have to be going somewhere, and you don't have significant control over where and how big that somewhere is (i.e. you can't easily move a whole urban center, or slice it into chunks and move all the chunks apart from each other a little to fit more roads). If all the roads are ending at the same place, making wider and longer roads to that place will (often) just induce more people to drive to that place from further away.

The reason "just shutting down all roads" doesn't make sense is that it doesn't solve the actual problem, which is that people want to both work in places with good jobs (traditionally often dense urban centers) while living in cheaper places that are far away and not spend significant chunks of their lives stuck in traffic. Shutting down all the roads only "solves" the traffic problem in a deliberately ridiculous sense (same as "just kill all humans").

Shutting down or tolling chokepoints lowers the opportunity cost of alternatives.

I work for a big central business district employer. You can pay $150-250 a month to park or $75/week to take a motor coach bus from your suburban town. Those numbers drive behavior, and make for a better solution as folks who need flexibility can pay for it.

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