Being able to backwards through the visuals is one major advantage of having the Sony Stalk Interface.
[But not the only one].

Its also on Mark Lords hit list of new features to add to the HIjack kernel real-soon-nowTM
[what it looks like Mark will end up doing is:
1. creating Fake Stalk commands to go Previous visual for those of use who have Tuners [whether or not we have a Stalk attached].

2. For those of us without Tuners, his kernel will pretend there is one there so that we can use #1 to go previous visual.
[Stalk commands come in from the Tuner Interface so you cannot fake a Stalk controler without faking a Tuner if one is not there].

If you ask Mark nicely I'm sure he can push it up the priority ladder a little.