[Elecraft] K3 CW rise time mod - Definition

[Gary Bartlett VE1RGB]

    I would like to see someone please take this discussion one step 
further and define the terms "hard" keying and "soft" keying, and 
describe how either an operator or someone listening would be able to 
discriminate between the two.  My rig is #095 and I frequently contest 
in the 30-34 WPM range.  How would I know if I'm guilty, if guilty is 
the right word,  of "soft" keying?!  Is this an issue only for those who 
are keying external amplifiers?

    73,
Gary, VE1RGB