I'm very sorry for rezzing this post. However, after looking all over the web I couldn't find an answer that suited my impatience. I believe I was looking for the same solution OP was looking for. Anyways, all you have to do is create a shortcut on your desktop (I guess if you're running linux you could create an alias in .bashrc?) and in the field for the location put: "F:\Curse\Install\minecraft.exe" --workDir "F:\Curse\Install" Please note: you will HAVE to change the filepath to the path relevant to your install of the curse/twitch client. Save your shortcut, and run it. Hope this helps!
It would take... significantly more than that to run on Linux, mostly because simply getting the Twitch launcher to install in the first place would require a MONO bridge and a conversion patch for OpenGL.
Mind you, it shouldn't be insurmountable, but on Linux, you're talking about converting from .NET to MONO and from DirectX to OpenGL.
Furthermore, while this might get you to launch Minecraft without the Twitch Launcher, that isn't going to let you launch any of the packs available ON the Twitch Launcher. To do that, you first need to get the Twitch Launcher to work, then download said pack. Then you would need to find the folder for the given instance it created and run it using a method similar to what you describe.
So no... not particularly helpful, but at least you get a gold star for trying.