Have you tried startpage=no -- the whole purpose of the startpage option is to put as many tables on a page as possible. Right now, in SAS 9.1.3, there is NO vertical measurement technique available for ODS RTF.
For example, in a DATA step program to the LISTING destination, you can count the number of lines per printed page, by generally, counting PUT statements or using a technique called LINESLEFT. However, the LISTING destination is a monospace font destination and techniques that work for LISTING do not work for ODS RTF, ODS PDF or ODS HTML.
Every word processor that opens an RTF file will control the page breaks (or vertical measurement) based on the proportional font of the document and how many lines -AT THAT FONT SIZE- will fit on a page. In addition, the word processor program (probably MIcrosoft Word) has to reserve space around tables for the table grid lines. A table rendered in proportional font Times Roman at 20 pt will take up more room on the page than a table rendered in proportional font 10pt on a page.
To further complicate things -- it would be possible for you to have 2 tables on a page in 2 different font sizes! The number of lines "available" would change in the between the two tables.
SAS does not RENDER the RTF file. SAS only creates the control strings that MUST be rendered by the Word Processor (Word) or RTF rendering program. In addition, the RTF document can be altered or changed by Word .dot templates or Word macros after the file has been created by SAS -- so 2 people with 2 different settings in Word, might see an RTF file created by SAS a different way (perhaps one person automatically applies a Word formatting macro to their opened documents and the other person doesn't).
In SAS 9.2, there will be a new "flavor" of RTF (different from the current RTF) that will give you more control over page-breaking. That flavor of RTF is called "measured" RTF. I still do not think you will have LINE-by-LINE control (such as counting each line) -- but you should have more control over some RTF capabilities, as described here:
http://www2.sas.com/proceedings/sugi31/067-31.pdf
In addition, there is a lot of excitement over Microsoft's announcement that they were going to support something called Open Document Format -- a standard for documents that was not created by Microsoft (RTF was a Microsoft created specification). You can read the announcement of the ODF adoption by the ISO here:
http://www.computerworld.com/softwaretopics/software/apps/story/0,10801,111130,00.html
And there's mention of possible ODS creation of Open Document Format output in this paper:
http://support.sas.com/rnd/base/topics/odsmarkup/Paper_227-2007_ODS_Office.pdf
However, that technology is in the future and won't help you now. Your best bet is to experiment with startpage=no for now or to contact Tech Support for more help.
cynthia
ps...in the ODS RTF documentation for KEEPN, there is this tip:
Although KEEPN minimizes page breaks in tables, it might use substantially more paper than NOKEEPN because it issues a page break before starting to print any table that does not fit on the remainder of the page. This statement implies to me that ODS RTF is internally doing SOME kind of "counting" behind the scenes in order to approximate what will fit on a "page" -- however, you cannot get to that internal code.