https://www.ifixit.com/Teardown/MacBook+Pro+15-Inch+Retina+D...
"MacBook Pro with Retina Display 15" Mid 2012 Repairability Score: 1 out of 10 (10 is easiest to repair)"
https://www.ifixit.com/Teardown/MacBook+Pro+15-Inch+Retina+D...
"MacBook Pro with Retina Display 15" Mid 2012 Repairability Score: 1 out of 10 (10 is easiest to repair)"
It's interesting to compare that machine to today's. 5.6lbs vs today's 16" at 4.3lbs. 2012 is 0.93" thick and today's is 0.64". I suppose, based on this datapoint, we can say there is something like a ~25% mechanical overhead for "repairability" then.
"MacBook Pro 15" Unibody Mid 2012 Repairability Score: 7 out of 10 (10 is easiest to repair)."
https://www.ifixit.com/Teardown/MacBook+Pro+15-Inch+Unibody+...
"MacBook Air 13" Mid 2012 Repairability Score: 4 out of 10 (10 is easiest to repair)."
"All the components—including RAM and SSD—are proprietary." Although I suppose there are probably 3rd party options by now.
https://www.ifixit.com/Teardown/MacBook+Air+13-Inch+Mid+2012...