Difference between streetcar and bus
Since many people still think that if you build streetcar, they will come; here's a set of use case-like tables which I hope will explain what the actual difference is between streetcars and buses. The first case is for "why can't we just fix commuter rail by building a streetcar line to which they can transfer?". The second case is for "won't streetcar get more residents of central Austin to take transit to work?".
Some shorthand below explained up here:
"Stuck in traffic": Does the vehicle have its own lane, or is it sharing a lane with cars? This affects speed and reliability.
"Detourable": If there's a traffic accident in the shared lane, can the vehicle in question change lanes to get around it? This is a drastic impact on reliability.
"Fast/slow": Is the vehicle capable of accelerating/decelerating quickly? Speed, obviously.
|Mode||Stuck in traffic?||Detourable?||Fast/slow?|
|Circulators as applied to commuter rail service|
|Mode by itself (for residents of actual central Austin)|
Notice anything? Whether you're using the vehicle as a circulator or as your primary form of transit, it performs exactly the same. I know this seems obvious, but I still get people thinking that there's some magic fairy dust that will make streetcars turn into good transit service for the people who actually wanted it, in both 2000 and 2004. No, credulous fellow residents of Central Austin, streetcar doesn't bringing anything more to the table than bus does - arguably LESS, for daily commuters. Note the "Detourable" column. Yes, I've had times on the bus when I've benefitted from this capability. They won't detour just to get around heavy traffic, but they darn sure will to get around an accident.
So what are some of the other benefits of streetcar not mentioned here? It provides a perception of permanence that bus service does not. This is worth something if you're trying to stimulate development somewhere - but downtown Austin doesn't need the help. It also provides a minor benefit for tourists - making it more obvious that transit exists, and making it more attractive (people from out of town are unlikely to want to ride the bus given the stigma of bus service in many other cities).
The only advantage streetcar has is for tourists - which is why, IF we build this thing, it should only be funded out of hotel/rental car taxes. Even if it ran through the dense residential parts of Austin, it would provide precisely nothing of benefit to those residents, who, by the way, pay almost all of Capital Metro's bills.