For reference, there's a Wikipedia page about this [1]. Mel is believed to have been Mel Kaye of Royal McBee Computer Corporation. There's a picture of him here [2], and the article the picture is from here [3].
We have all met someone like it. A colleague who now works in accounting because of his dislike of all modern programming practices is maybe not Mel-class, but I have yet to meet anyone who can read hexadecimal with his speed.
In the late nineties he apparently found a bunch of optimization errors in the compiler the company used by spending an hour reading through the machine code. I have seen him read machine code once, and it involved him scrolling by holding the down arrow and stopping every 50 rows for 2 seconds. He not only found the error on the first try, but also found a couple of potential bugs.
I remember reading this back when the "Hacker Jargon File" came as a package with the Debian distro (probably on the second CD.) I wonder if the Jargon is still maintained at all. With the current trend of constantly-changing overloaded terms it'd be quite the undertaking.
[1] https://en.wikipedia.org/wiki/The_Story_of_Mel
[2] http://zappa.brainiac.com/MelKaye.png
[3] http://www.librascopememories.com/Librascope_Memories/1950_-...