Simply put, no.
Take for example, you install the bits for the service pack 1 upgrade. The first thing, of course, is that you need to finish installing those bits on all of the servers in your farm. But then after that you need to run the SharePoint Products Configuration Wizard (or run psconfig.exe) to upgrade the installation. I recommend running the wizard first on the app server that serves your Central Administration site. But you really need to wait until it’s finished before running the config wizard on your next server. If you do rush ahead, it won’t let you. I tried it just to see what would happen. When I started the second config wizard in the process, the screen stayed just like this until the first server was finished with the wizard.
So it looks like there is a flag that is checked before it starts. And if one server already is locking up the configuration, the next one will not start until the first is finished.