Relationships spelt out in building phases?

My co-worker made an interesting analogy today while driving me after work to Jawn's office. Thankfully I didn't have to take the subway today...phew! And yes, going to Jawn's office after my work also meant that he has to do OT today. I also realised that the number of times I post on the blog by myself were the number of times Jawn did OT. Oh I must also make another comment: this is the first time I saw an electronically operated seat belt in my whole life, cool! (basically with the touch of a button on the driver's side you are clicked on). It's probably not a big deal but considering the fact I have only started commuting in a car (taxis not included) on a regular basis at the age of 23, this is something revolutionary to me even though it's not a new technology.

Anyway(s), the analogy my co-worker made was that he analysed relationships in terms of building phases...not that i totally agree with it, but it's funny how he rationalised relationships to that extent. I think it's the occupational hazard. He said he's in 90% SD with his gf, (ok before I go further, let me explain the abbreviations used daily in the architectural field).
SD - schematic design (the first phase of design),
DD - design development (when some details are drawn),
CD - construction documentation (the package prepared for construction),
CA - construction admin (construction has begun and we deal with on-site issues).
So in his terms, DD is when you are officially dating each other, CD is when you are engaged and preparing to get married, CA is when you are already married.
According to him, one of our other co-workers is in 110% DD (i.e. should have been engaged long ago but not yet), while jawn and myself are in CA. I told him in a marriage we'll never be done with CA though. There are always areas for fine-tuning and things to work out.
Hmmm...