I never disconnect, decouple or preserve. When I am done with my project and say going to bed or whatever I just close Logic entirely and it closes all my VE Pro sessions for me.
When I want to change songs I do a file, close project. Then file open and grab the project I want to work on. VE Pro closes my other sessions and launches my new ones automatically. I don't use 30GB templates and projects so it takes about 1-3 minutes for it to load all the VE Pro instances for my project but I don't care, it's not bad. And the actual project itself opens instantly, I just wait for VE Pro to get done loading my vframes.
When I am done I close Logic entirely and VE Pro automatically closes all of the open sessions. I wake up the next day and have absolutely no issues opening the project at instant speed, no matter where (home or office) as long as the last VE Pro server I connected to was a slave and not my local machine.
Maestro2be