[Elecraft] K3: too easy to overwrite dial memories

[Eric Scace K3NA]

   In the world of ergonomics and man-machine interface design, there is 
a rule:  If an action will destroy information  or a state than cannot 
be restored with the same effort that it took to destroy, then the 
system requires either (a) a "Un-Do" function of equal simplicity, or 
(b) a confirmation step.

   The choice between (a) or (b) depends on the consequences of the 
unintended action during the time it takes to recover.  For example, a 
(hypothetical!) button that shuts down the jet engines on an aircraft 
requires a confirmation step... because turning off the engines until 
the pilot hits UnDo would be bad!

   This rule applies to software as well as hardware.

-- Eric K3NA