"Losing itself" meaning here that it forms a scope much larger than that which it existed within for so long. Your commentary is spot-on about so many things (Pee-Wee especially), but never is it so pointed than when you elaborate on the expansion of the entire metacritical universe in which Garfield exists. To be more specific, you say:

This is PRECISELY what I think this series of strips was created to accomplish. If we take this week of "Garfield" as the fulcrum on which the entire history of its character's lives rest, we can consider it to be that which every frame of "Garfield" not a part of this series can be compared. Suddenly, the characters within the strip have an implied history, & one that is uncharacteristically philosophical, & humanly (some would argue) unthinkable. This is where the genius lies: Davis, in creating this specific series, is not only poking fun at cartoon syndication, but is tossing the entire idea headlong into an extremely existential argument, which is this -- why are these characters here, & who are we to have ever created them? And, perhaps more importantly so, does their existence hinge on our artistic rendering of them?

Having read this series from '89 over & over again, it becomes more & more obvious that every other "Garfield" is a constructed, patented lie that exists solely in an imagined space. But...the more you consider this...the more clear it becomes that this is a basic assumption that we as readers make about EVERY comic we read before we even begin to read them! Davis simply pointing it out, flipping it inside-out, & rubbing it in the reader's face.

& also: this is the first time I had come across it in color, as well, though I actually think the color version manages more visual depth & implied meaning, as well (with frames like the close-up of Garfield's eye, which I consider to be the coolest frame of the whole week).