mettelus
Not only do I have the Saffire set to be given exclusive rights (in Win7), but X3 is also not checked to "Share drivers with other programs." After I inadvertently did this twice, I started to intentionally do it... and they ALL will play simultaneously through the Saffire.

I believe the issue is not that you can't have multiple applications simultaneously using the same ASIO driver/interface, it's that you can't use two or more ASIO divers/interfaces at the same time (unless the drivers support aggregation).
 
With my single ASIO interface I can have Sonar playing back music then fire up a stand-alone Z3TA+2 and play along.  Both are using the same ASIO interface (and in my preferences, the share drivers is not checked).

Just learned something new, thank you! I searched "ASIO Aggregation" and it only returns one driver data sheet from AudioScience drivers. Section 5.3 (of their drivers) says "The adapters need to be all of the same type and use a common sample rate clock source when aggregating into one ASIO device." This is the same feature I stumbled upon with the Saffire by accident.
 
I ran back through the Saffire manual, and the only comment I could find was a Saffire setting to shut off other system sounds: "Disable WDM Audio in Windows (Windows Only)  Tick this option to ensure that only audio from your DAW is played through the Saffire PRO 24 DSP. Windows sounds will not be played through the Saffire PRO 24 DSP. Sounds from other software will not be played through the Saffire PRO 24 DSP. This is useful to prevent any unwanted audio being heard when you are working in your DAW. It is especially useful when other applications output audio at a sample rate different from the sample rate at which your DAW is operating."
 
I have Win7 locked to the onboard audio, so ancillary programs always sound through that, making the "disabling anything" never an issue for me. I just never knew of the "aggregation feature," which is incredibly nice.
 

I don't this is a universal feature, or at least I can't have both Sonar and Sibelius use the E-MU card's ASIO. I get around it because it also supports WDM and can do both at the same time.

I agree, I think this has to be scripted into the ASIO driver. What I find ironic is that Focusrite makes no comment that they have done that! My god, what a sales pitch that is (for me anyway).

Disable WDM audio in windows option is no longer available... Why? Because Focusrite made that option automatic, so you don't need to worry about it.

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