An MD80 addressed confusion inherent in the wording of Boxed and Ball notes on the RODIO ONE RNAV STAR to SAT.

Narrative

RE: RODIO ONE RNAV STAR into SAT. The [boxed] notation at CRISS intersection is confusing. The note there says 'LANDING OTHER THAN SAN ANTONIO INTL RWYS 3; 12R; 30L'; but ball note 3 also refers to 12R and to go over CRISS [and 'depart CRISS heading 295 degrees']. (Ball note 2 and 4 are for runways 3 and 30L and have different segments on the arrival).The language seems like a contradiction and is confusing to me. It would make more sense if the boxed note said 'OTHER THAN LANDING SAN ANTONIO 3; 30L' (remove the reference for other than 12R). What is more confusing is that the ATIS [often] says landing 12R and 30L. So when we load the landing runway into the GPS we really don't know which runway they will give us. We normally get 12R; but that might be an inaccurate assumption at certain times and the wrong runway might be loaded and the wrong segment flown than what ATC is expecting. ATC ultimately gave us a heading out of MARCS intersection; so it was not a problem; however; a late handoff or lost communication on the frequency could cause a problem and the wrong segment flown.