What is "diskless VDI"?
Do you mean using SSD drives or cache in the individual hosts (rather than shared disk) for replica / desktop storage? Usually folks then use profile/folder redirection in an attempt to create truly "stateless" images? If a host fails, no worries as long as there are other hosts also offering these same desktops, nothing is lost.
Is that what you mean?
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"I like flaws and feel more comfortable around people who have them. I myself am made entirely of flaws, stitched together with good intentions."
Augusten Burroughs