As for Engagement vs Immersion, it kind of has to do with how the players approach the game experience. In immersion (and presence), the rules of the game are supposed to fade into the background and seem like part of a “Real” world. With engagement, players are usually more interested in bringing these rules back to the forefront and trying to understand and master them. For example, the WoW players in the classic “Leroy Jenkins” video clearly maintain no illusions of being in a fantasy world. They aren’t trying to experience what it would “really” mean to be a paladin or a wizard, they are trying to understand the rules of the game so that they can win (except maybe Leroy, who seems to have a much different idea of what it means to play the game). Certainly none of these three experiences are mutually exclusive, but there is a lot of give and take when design decisions are made.

As for the relationship of flow to these three concepts, I think that it is certainly think it is important to all three. Though perhaps most closely linked with engagement, in the sense of getting “in the zone,” maintaining flow is important for maintaining the illusions of both presence and immersion. A break in flow resulting in frustration, for example, reminds the player that she is participating in an arbitrary and perhaps unrealistic ruleset or interacting with a piece of machinery that is less responsive than she wants.

I don’t think any of these experiences are intrinsically good or bad (which is not to say that they couldn’t be used for either), but people definitely prefer some over others. While plenty of people seem to think that 3D-IMAX-Smellovision is the way of the future, I find I am able to “get into” a normal 2D movie much better.

Anyway, on to the comment:

I think I would be much more comfortable with flow if it was separated from immersion. I’ve started to become very worried about what immersion might actually mean as it applies to the subjectivity of the ‘body’ in regard to the overwriting process the system is doing to it. That it might be /over/writing, through the suture moment, the player’s true agency.

The following words especially are worrisome to me: “fictional world replace the player’s real world.” I know that, for what feels like a long time, that’s also been the ideal situation, but the more I think about it, the more that seems, I don’t know, /weird/.

We want the player to forget their ‘body’? To be subsumed into the world of the game? Isn’t that, to put a value judgement on it, “bad”?

I also agree though, to shift gears slightly, that the flow channel poses a problem with interpreting it as increasing levels of mastery corresponding with difficultly. As per your knitting example, yeah, it doesn’t make sense. There is a plateau reached where the knitters can comfortably control the situation.

Bringing that back to games, it suggests a problem, and this is what I linked to in Robert Yang’s talk on immersion too, that flow should be associated with difficulty somehow. Yet, flOw clearly isn’t that. Nor is Flower. Both games most often links to that concept, both through design and conversation.

I’ve also got more to write on constraining choices, touching in the post “The Tyranny of Choice,” but I should probably not make this comment too long.