It seemed to be pretty random, almost as if it were unique to each keyboard (which was, if I recall, how it was described back in the old key configuration utility included with the DOS version).
PC keyboards have their own microcontroller to handle key scanning and reporting key events to the computer, so you can hook up the keys pretty much any way you like. Most keyboards use a matrix-like structure in which, essentially, voltage is applied to each row of keys in turn and each column is checked. The keys themselves are on the intersections between rows and columns.
The advantage of this is that you don't need a 104-input (or whatever amount of keys you have) microcontroller to check key states, just one with enough outputs to the rows and inputs for the columns (e.g. 6 and 20, respectively). You also don't need anywhere near as much wiring between the keys and the controller. However, by wiring each key individually, one could build a PC-compatible keyboard with no jamming problems whatsoever; it would probably be something like twice as expensive, though, at least (even worse if it isn't mass produced like normal keyboards).
If there were more applications that suffered from keyjams, or if keyjams themselves resulted in more horrible consequences (aircraft control systems don't keyjam, for instance) we'd probably have our perfectly wired keyboards. As it is, keyjamming remains a plausable but very, VERY cheap star control 'tactic.'
It IS kinda funny though...
« Last Edit: July 11, 2006, 12:30:05 am by Holocat »