Also keep in mind, that the MythTV function of LMCE is exactly like the Stand alone version. If you have multiple MD's hooked to the system, each one has a slave backend built in, so, the core will push commflag jobs to any other systems (MD's) that are inactive or using less CPU.
I have 4 MD's, and I can pull up the backend status on mythweb, and usually the job hosts are the MD's, leaving the core to have full power for everything else.
My commflag jobs run first, and are then followed by the "Save Recording to Pluto DB" job as well as my "remove-commercials" jobs. Because all 3 jobs run one after the other, the core usually offloads the processes to one of the MD's in the house not being used, or being used very little.
So the more MD's you have, the more the commflag and any other UserJob you schedule from MythTV will be pushed to MD's to save CPU power on your core, or core/hybrid.