Thanks to Sam and Julia:
Sam for bringing up the idea in the first place, Julia for dragging me into it.
I am no academic, so I won't attempt the rational style.
Unlike (the common picture of) reality experience dilates according to some nameless quality experienced by its experiencer.
The sole salient feature of all such qualities is their dilating effect upon experience therefore I name this quality synecdochally after its solitary object: Dilation.
Dilated experience is experienced more and though there are many comparative adjectives we might suggest (greater, richer, catchier, stronger, heavier, larger, better) moreness answers for them all perfectly without any unnecessarily exhaustive list.
A work of art dilates according to its artist's or artists' process.
Art dilates, governed by process.
In collaborative storytelling we collaborators decide how the story dilates: why do some events take months to tell, and others minutes?
We may be able to find a more precise understanding of this dilation through analysis, but it will remain true throughout that process, exclusively, determines the dilation.
Does dilation act upon experience, or produce it?
That answer is ontologically and semantically unclear to me but as dilation determines how we experience experiences it plays a pivotal role if not the superlatively most role.
"Games are a series of interesting decisions"
Interestingness is effectively synonymous with dilation and comes with all its baggage.
Games are full of uninteresting moments and nondecisions but Meier elides these as nonexistent.
The quote describes games as its interesting decisions rather than defined by them.
Then it follows: Experience is a series of dilations.
Dilatedness and interestingness are spectra not binaries yet I can only find their usage in "is" above distinctly binary.
I am willing to accept this not as a threshold but some other nearly mathematical trick.
A decision "is" or defines its game equal to the decision's dilation.
An experience or subexperience "is" to a degree that equals its dilation.
The more specific problem is that of artwork rather than all experience.
I will focus there.
In Handmade Pixels Juul writes that certain theorists worry goals and optimization "shift the player's focus away" from other things and I argue this is explicitly a concern about dilation.
~ Handmade Pixels, "dual worries" about goals and optimization in games (http://newforum.droqen.com/index.php?topic=413.msg1919#msg1919)
If dilation defines experience then it plays that same defining role in art.
A work that shifts the player's focus towards goals and optimization is defining itself by those things.
Finally I can arrive at the crux of my argument regarding dilation:
To design a game about anything,
that thing's experiencing must be
dilated in the player's experience.
Satisfying mechanisms emerge from systems built upon metaphor or feeling; goals and optimization make them instead games about those "unintentional" mechanics.
The infectious nature of fun in that described above does not belie a meaninglessness but originates from its compellingness and very disposition towards dilation rather than any meaningfulness or relevance.
In the hierarchy of dilation a subtler feeling can be overshadowed by other feelings more readily dilated.
Dilation defines experience and process determines dilatedness.
Dilation is neither virtuous nor sinful.
Just take care with dilation that the deep feeling is not lost to those experiences which have a greater predisposition towards dilatedness but are ultimately wrong.
The goal is not perfect dilation of that deep feeling.
The goal is a process which at each step enhances dilation of that deep feeling and never loses its way.
Each such step may also be known as a structure-preserving transformation.
Local maxima are not fail states.
They are vantage points.
They are homes.