On Jun 18, 9:09 am, Jeff wrote:
http://americanart.si.edu/maloof/design/fig171.jpg

Maloof appears to pin the crest rail through the back legs of that
chair. I can understand why he'd pin the chair rail tenons as a
drawbored M&T is quite sturdy indeed. But when he pins the crest rail,
he's boring through end grain. I would think those pins would weaken,
not strengthen, then chair. Then it occured to me. Maloof's not
pinning the crest rail tenon. Despite the round ends, those aren't
pins he's using. They're wedges.

That's just a guess. Am I right?

My local library's got a video on him. Watched it with the wife and a
friend. Outside of the "Wow!" factor as we watched him sail that wood
through the bandsaw at all those odd angles, we remarked on all the
screws he used putting those things together and some of those were
into end grain and then plugged.

I can't tell from that photo where you're talking about, though.