We are going down a similar path to several other folks using an ADV761x device, but needing to support WUXGA (reduced blanking). Most have been referencing the ADV7611. We currently have the ADV7612 Eval board, and will use the ADV7612 for proto builds, but plan to drop to the lower power ADV7610 for production (several 100 mWatts less). However, I just want to confirm that the HDMI/DVI front end is effectively the same in all the ADV7610, 11, and 12 and therefore the use of a "reserved" register setting (i.e. with PRIM_MODE = 0x6, set VID_STD = 6'b011001 (0x19 hex)) is valid to support WUXGA (1920 x 1200, 60 Hz, reduced blanking).
Do you have any info on when the documenation may see an update (or a quick App Note) as using "reserved" settings will cause someone to ask if that is a wise thing to do and what is the risk that support could just be removed in a future silicon spin.