Can Symphony I/O be connected to two Mac Pro’s at the same time, one for Symphony and the other for Pro Tools HD?

Even though there are two Symphony ports on the rear panel of Symphony I/O, only the ‘MAIN’ port can be connected to Symphony 64 or the Pro Tools HD Core card. Therefore Symphony I/O cannot be connected to Symphony and Pro Tools HD at the same time, whether it be one Mac Pro or two. Functionality for Symphony I/O’s ‘THRU’ port has not been enabled.