How hard has he been working in recent weeks toward this deadline? There has to be a burnout factor in here as well.

Otherwise he's sending you a very public signal that he's checking out. Or he's bored, and bored people quit:

http://www.randsinrepose.com/archives/2011/07/12/bored_peopl...

I tried offering equity and a slightly lower salary (20%-range lower), and then an option for no-equity but higher salary. He took the higher salary option, though I was hoping he would take the equity option.

I could revisit this with him...but I have a feeling it's not super important to him, money doesn't seem to be a huge motivator.

You offered him 20% less money and some percentage of nothing? Are you really shocked he didn't take it?

If it wasn't your company, would you "spend" $15,000 on the equity you offered?

Exactly. Every startup I've worked for the owners have this weird attitude that their equity is worth something. It's not. It's worth jack shit until the company is worth something. It doesn't pay bills. It doesn't let me buy the new shoes I want. It's essentially an investment. Usually if someone is in the position to invest, they don't need to work a day-job to cover bills.

Ahem, it's not a "weird attitude" to offer less salary in return for equity. Of course equity is worth something.

Not shocked, I was a little bummed.

Would you recommend just granting some equity to try and engender the "ownership" aspect?