So it looks like we might need to do a bit more work on the documentation.
I'm not really sure which aspect you're having trouble with: the pre-generation of the quickstart war or the use of the webapp afterwards?
If it's pre-generation, you don't necessarily have to do a special step in the generation of your webapp to generate the quickstart-web.xml. Instead, you can just let jetty lazily generate the quickstart-web.xml when the webapp starts for the first time. To do that, use the instructions on the doco page you linked and follow the section "In XML". The "autoPregenerate=true" will tell jetty to generate the quickstart-web.xml if it isn't already present. When it generates the quickstart descriptor, you'll see a line like this on startup:
INFO:oejq.QuickStartDescriptorGenerator:main: Quickstart generating
You'll know its faster if you have any annotations in your webapp and a lot of jars in WEB-INF/lib, because it will be noticeably faster to start ;). Without the quickstart, or when it's lazily generating the quickstart for the first time, you'll see a line like:
INFO:oeja.AnnotationConfiguration:main: Scanning elapsed time=xxxms
On subsequent restarts you won't see that line.
As the doco mentions, there is a goal of the maven-jetty-plugin that uses quickstart to generate an effective web.xml for you - if you want you can save the output of mvn jetty:effective-web-xml into a file called quickstart-web.xml and put it into your webapp, but that would be a bit of a manual process.
Sounds like it would be useful to have a maven plugin that did the quickstart generation as part of a webapp build cycle, don't fancy contributing one do you? :)
cheers
Jan