[BugsJustFindMe]

But they don't explain what metrics they use to differentiate skill level other than waving the hands of a puppet coach. The arm control is great but they don't show it returning non-softballs. Is that what "intermediate" means?

[spongebobstoes]

Probably, if you consider that a beginner can rarely volley at all. At an intermediate level, a fast return pretty much just wins the point, when it doesn't hit the net or miss the table.