I spent an hour chatting with Adobe support in India. They could not solve this issue.
I submitted a BUG REPORT at Adobe - Feature Request/Bug Report Form
Here is the BUG Report:
******BUG******
Concise problem statement:
Steps to reproduce bug:
1. Export individual pages from InDesign as pdf (16-page booklet, each individual page is 5-1/2" x 8-1/2")
2. Open pdf in Acrobat Pro 11.0.10
3. Choose actual size, then choose booklet, and print. (printer contains letter-size paper, and page set-up is set to 100% scale.)
Results: The printed booklet is the WRONG SIZE! The pagination is correct as usual, but each individual page is being REDUCED, and now each page image is too small, and there is now a GAP between pages, and the entire booklet is useless. If you can, please see case number: 0186447426: support chat: it covers everything we have tried so far ... (We tried everything they could think of, but all attempts failed.) This bug was introduced somewhere along the line with Yosemite.
Expected results: As usual, when printing booklets from Acrobat Pro, we expect the print to be the right size, the same size as the InDesign doc, and as it has been printed previously by Acrobat Pro prior to Yosemite. Thanks for fixing this disaster of a bug. Please contact me if you need further info, copies of the individual page pdf, etc.
I am literally stuck. I can go through the laborious process of using InDesign to "print booklet" to a postscript file and use Distiller to make the booklet pdf, but under Yosemite, I am prevented from installing print drivers unless that printer is locally available on my network. Unfortunately, the printer is located at my client's place of business.
I realize there is typically a leap-frog effect between operating system updates, hardware, and application updates, but combined with other Yosemite issues, this Acrobat Pro bug is killing my business.