As a game scales further towards a narrative, randomness must necessarily decrease. We have two models on opposite sides of one another and a sliding scale that lies between them. On the one hand we have life, infinitely complex beyond the analysis of anyone, man or machine. On the other hand we have things such as novels, which must necessarily be less complex than life. Indeed, novels are a frozen set of choices: they never change, no matter how many times you read them. That's not to say that there aren't stratified layers of meaning that can be unpacked, that books themselves do not contain an infinitely deep amount of information.
I think this is a good way to classify the distinction: depth versus breadth. Novels are very limited in breadth due to the nature of their construction. They cannot typify a wide variety of inputs. Indeed, they are only good for one input, that which the author has created. This is, of course, discounting the interaction between reader/author and the interface between art/viewer. For the purpose of this argument, however, novels are deep rather than broad. They have themes, motifs, movements, and other indicators of depth.
Old school games (non-storytelling games) are broad, rather than deep. No one looks for the leitmotif of an AD&D game because that is not a question that the game addresses. There are no themes, no poetic justice, really no literary devices of any kind. The reason for this is, of course, the fact that they are infinitely broad. The scope of the game is unlimited, which means that any message developed by a literary device would be lost amongst the myriad trivialities of every day life as experienced by the PCs, even if the DM wanted to include one.
There is, of course, in the Deconstructionist sense, a single overriding theme in a broad game. Namely, the uncaring nature of the universe, the randomness of human experience, etc. But that is the only theme that can be present because the game, like life, is so complex as to defy the classifying structure of literary and dramatic criticism. Namely, things happen not because they reinforce a particular point or serve as a metaphor or device, but rather simply because they do.
There are storytelling games where motifs can be developed, random encounters are done away with, tables are minimized. White Wolf's games, for example, fall distinctly into this category. They no longer seek to emulate a broad experience, but rather a deep one. There's nothing wrong with that, save that the natural powers and inclinations of pen and paper roleplaying games tend the other way. That which is proper to a novel is not necessarily proper to an rpg, so the game becomes some manner of hybrid between story and game.
The allowance for random interference increases the closer you get to life and decreases the closer you get to story. Indeed, even novels or games with a high appearance of randomness can be completely (in the case of a novel, must necessarily be) locked along a fixed path wherein the randomness only serves to further illustrate a point. This is the dreaded illusionism which many OSR proponents, including myself, reject as a method of controlling the game.
Deep games can be fun, but they are fundamentally different from broad games. Games that attempt to masquerade as both are terrible. It is an essential lie, an irreconcilable difference between two utterly contrary modes of playing, and I have never played in a game that attempted to emulate the feeling of breadth with the control of depth that has not made me want to claw out my eyes.