The only time I can see that is if the user is doing a custom check-in and has selected to generate models and viewables. The viewable is then generated on the user's machine, not the publishing machine. When we do this, it also ties up the Creo session as it pages through the drawing sheets. This would prevent the user from doing any work until the local publish is completed.
I cannot think of any thing that would cause a publishing job on a remote computer causing the local computer slowdown except maybe downloading a new assembly to work on since the Windchill server is locating and 'feeding' 2 workers. But each session should be on a dedicated method server, so it would depend on the number of method servers and cpu cores you have on the Windchill server.
I have 2 hex-core processors (Hyper-threading disabled) with 36GB of memory on my Oracle and Windchill servers. When we first installed them, we moved the 9.1 Oracle over from a 2-cpu machine with 4GB of memory. The users noticed the difference immediately. After the upgrade to 10 in 2014, they noticed things got even better since 9.1 had also been on a 2-cpu/4gb machine. Now on Windchill 11.0 m030 with my own issues with publishing.
