OK, here's what I've uncovered: In a nutshell, I've been able to narrow the problem down to my PS3 and how it's communicating with the 805 via its EDID commands when 1080/24p material is played. With my PS3 set to 1080/60p, I found (quite accidentally) that I could play my A35 at 1080/24p with no pass-thru issues (blacks remain solid and deep--as deep as LCoS is capable of, naturally--with all applicable sources). However, everything goes haywire the moment I set the PS3 to 24Hz, at which point 24Hz playback from both sources result in elevated black levels; the blacks become a noticeable dark gray. Somehow while in 24Hz mode, the PS3 was sending information to the 805 that affected all its HDMI inputs when an incoming 24Hz signal was received. This result is what led me to keep everything at 60Hz. (Keep in mind that all of this was a non-issue when each source bypassed the 805 and went directly to the display.)
Once it became clear what the source of the problem was (in relation to the 805), I settled on the PS3 at 60Hz and the A35 at 24Hz, with solid results. And I was fine with it. But after a while, this pseudo limitation started to mildly get under my skin. Why have 24Hz-capability and not be able to fully utilize it from all sources, know what I mean? Long story short, after days of experimenting with various settings on the PS3, something quite surprising happened: When I switched the PS3's 24Hz setting to Automatic (as opposed to On) and turned on SuperWhite, HOT DAMN!!! Dead-on, ink-like blacks from all sources regardless of refresh rate. Whether routed through the 805 or sent directly to the display, the resulting PQ was equally stellar. That did it!
To make sure this wasn't a fluke, I also experimented with the two of the three other 805's I have access to (via family and friends). I immediately recalled that I used my PS3 when I tested their units earlier (they don't yet own one). Both of them own the same display as I, which helped tremendously. To my delight, with the PS3 set to SuperWhite=ON and 24Hz=Automatic, I got the exact same result! The final test was done last night when I borrowed a friend's Panasonic BD-35. With the PS3 completely out of the equation, 24Hz playback from the Panny and my A35 was solid and problem-/anomaly-free. So clearly the PS3 talks to the 805 in rather strange language when it comes to 24Hz playback. But changing those settings accordingly solved my problem when passing the signal thru the 805. All is right in the world again, and now the system collectively is operating at full potential. (I knew the issue wasn't my imagination! And yes, there have been a few service menu adjustments made to my A3000 as part of a thorough calibration--including the gamma adjustment--non of which had anything whatsoever to do with the problem.)
From my vantage point, I can now wholeheartedly vouch for the 805's video pass-thru performance. Speed Racer, How The West Was Won (SmileBox version), and The Incredible Hulk at 1080/24p are indeed "sick"!