For your question - yes I know how it works.
Have I done it myself? No.
Is it a trivial task for an average user? Probably not.
Before going anywhere, I would like to elaborate on the 'impracticality'.
The impracticality here meant that I see no reason for someone to take the effort to do it unless:
a.) The SSD module is busted out (Highly unlikely - given they're Flash based)
b.) Someone felt like having a storage upgrade. (But to my knowledge, replacement SSD module for the Macbook air and Retina MBP does not come by easily. Therefore also rather unlikely)
Now, for my 'misbehavior'.
I admit that I was being a jerk, and have been rude. And perhaps I took things a bit too far. Yes, I was a little harsh, insensitive and/or not considerate (enough). And As I said above, for that I am truly sorry.
It seems that people are taking my initial post as me trying to be a total jerk. My intention was to just 'sting' a little. And as I said above, perhaps I have taken it too far.
I believe that we share different views in regards to at what point a question becomes 'a stupid one.' For me, I googled things up real quick before I clicked 'submit Reply' just to cross-reference and was able to confirm that what I composed as my first response, was in fact true (well, at least in the way I intended to say it). I used a metaphor just to tell jeejeebu that swapping the module is pretty much impossible. It seemed like a few people took it the wrong way. For that too, it was a miscommunication from my end; for that I apologize as well, and am clarifying at this moment. I also will try from now on to avoid such language so a miscommunication like this would happen at least less frequently.
I have tried to handle this in a as mature manner as possible, and I hope that you do the same - take my apology, and leave it as is.
P.S. I have already apologized once - I don't think you have to bash me for it again and again. And taking bits out of my post to suit your needs is not an honorable way of approaching things.