Enabling "Accelerated 3D Graphics" in Fusion will render Citrix Viewer inside a Windows VM completely unusable. This is a long standing issue: Fusion and Citrix performance terrible (as in not even able to reboot VM)
Disabling "Accelerate 3D Graphics" has obviously some CPU side effects, which not everyone can live with.
I am not clear on whether it's a Citrix or a VMware issue to be honest.