Measuring Emotional Involvement in Games

Just reading the interview with Doug Church of Ultima UnderWorld, System Shock, Thief fame in Richard Rouse's Game Design book and grooving on what they were saying about the high emotional intensity of more scripted games (CoD, MoH), versus the greater memorability, but higher risk of more open system games (GTA) and again it takes me back to playing Red Dead Redemption and feeling that there was some great stories and subplots in there, but that sometimes too many of them were thrown at me at once.

I was just thinking again about the mission I got to go save some missing boy, and how when I wandered off in the direction I thought I was supposed to go how I bumped into some prospector mission thing and then a stop-a-lynching mission which got me killed, with both the latter sub-plots seeming unrelated, and I started thinking how maybe I had gone off in the wrong direction and so I was implicitly telling the system I wasn't interested in the lost boy sub-plot (although I think I had accepted the mission), and wouldn't it be great if there was a better proxy for games to tell how emotionally involved a player was in different sub-plots. Of course we're still a ways off from measuring emotions with electrodes, but I wonder if some proxy or correlate could be extracted from game data - although of course that is at least partly what balancing a game is all about.

Of course the reality of real life is that all sorts of "sub-plots" keep popping up and getting in the way, but reality can often conflict with having a good narrative. In the first instance a simple heuristic for keeping track of the number of sub-plots being thrown at a player might be good, however surely RockStar will come up with this and more and throw it into their latest and greatest, and I am unlikely to be hired as narrative consultant any time soon, and I don't have the resources to make those sorts of games, but I wonder if text based narrative games could be made to take advantage of this idea, which brings me back to Zach Tomaszewski and Marlinspike, which I think I really must implement a game in ...