Sorry, long weekend. =) It was pretty busy too.
I would suggest creating separate pools to allow for VMs with different CPU/Memory instead of modifying them directly. If I'm not mistaken that's not supported, even though in certain situations it can be done. Simply clone your parent VM and modify its CPU/Memory to where you want and create a new pool using the new parent. Modifying your View VMs directly is a practice that's best to avoid even if it does sometimes work.
And to answer your question I believe that yes, the lock when you try to modify is related to the fact that the VM is essentially just a snapshot of it's Linked-Clone parent.
~Brandit