I'm here to report a data point and it's good news.

I had to do a DS-11 full application in person to replace my lost passport book. I paid for expedited processing and expedited mailing.

Submitted at Cook County Court in Chicago -- no appointments, 15 minute wait. I applied for normal book + passport card. (DS-64 reporting lost passport was submitted online when DS-11 filled out, around Nov 7)

Nov 12: Submitted application at acceptance facility
Nov 22: "In Process" (code 42 -- New Orleans)
Nov 23: check cashed
Dec 3: "Approved" (expected arrival date Dec 8)
Dec 3: Mailed via 1-day Priority Mail Express. Return address says "New Orleans" but tracking number said it originated in Tucson.
Dec 4: Passport book (old "e-Passport" style) arrives in my mailbox.

Total: 22 days (3 weeks + 1 day)

Basically 1 week to get there, and then 2 weeks to be approved, then fast next-day delivery.