Scrubs-Erfinder Bill Lawrence erklärt, warum Elliot und J.D. in der letzten Scrubs Staffel wieder zusammenkommen sollen recht einleuchtend in seinem Blog:

Okay, here was my thinking. There was massive argument/discussion between writers/cast/wife. Ultimately it came down to this - I wanted, at some point, to sleep with my wife again…
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So, I hope the shippers are happy, I hope the others don’t feel betrayed, but those are my reasons.

And, of course, the sex with my wife thing.