So controller says "...that is incorrect. All entries in the arc from
Volan to Mercy are NoPT!! So where does that come from?

Where the sun doesn't shine most-likely. I've never heard of such a thing,
but as others here will attest, I'm no great source of wisdom. As I look at
the plate ZARTO is an IAF and that is where you were sent. There is no
where listed on the chart that NoPT is required of ZARTO.

No matter who's correct here, if I was NW of the AP I would have proceeded
with a parallel entry at ZARTO. If the turn was just right and my altitude
ok I would have proceeded immediately with the approach once back at ZARTO.
After all once cleared for the approach and you are established on a
published segment of the approach, you can proceed with that approach.
Correct? I guess my question is: After the parallel entry, even if one's
altitude and line-up are perfect at ZARTO, is one complete circuit around
the hold required anyway?

Kobra