So humor me on this. If they were able to ad that in a firmware update why cant't sub trim be added. There are plenty of buttons that I will never use on that remote that I would be able to reassign.
There was already a function in place (button on the remote that brought up sync adjustment in an on-screen pop-up) that simply needed to be duplicated on the front panel. I don't know how "simple" the actual programming was, but the infrastructure was in place for it from the beginning.
Adding sub trim would require a command to bring up sub trim adjustment, something that doesn't exist presently -
that is the underlying problem we're faced with. Where would that command come from? How would we tell the 990 that we want to adjust the sub trim? If they added a completely
new IR command for this, the only way for people to use that command would be for them to have third-party remotes that would allow them to download some new data and upload it to the remote. My MX-700 could do this, as could Prontos and Harmony remotes (by way of some coordination between Outlaw and Harmony), and folks who do JP1 programming of UEI remotes could pull it off too. If you were using the 990's stock remote or a third-party universal that didn't support a computer interface, there'd be
no way to use that new command - Outlaw would in effect be saying "here's a neat new feature, but we aren't going to let you use it unless you happen to also own an expensive remote and can configure it to send a new command." The other alternative is to re-assign an existing command, which presents two new problems: the button on the remote doesn't match the function (at which point Outlaw would be saying something equivalent to "Press PRESET SCAN to change DTS surround formats") and we have to give up some
other command that people have already gotten used to having available. You may not mind giving up the night mode button, for example, but there are likely to be at least as many users who want that button but have no interest in a sub trim button as there are users who want a sub trim button and could live without the night mode button.