Fighter:
You do not need a security expert for the answer. As you have guessed a keylogger would then only log "CTRL + V" for the Paste that you are doing (and the CTRL + C that you copied from). You have therefore fooled the keylogger.
However, you have introduced a new problem of...
jck_2378:
TDWaterhouse's goal is to prove that it is not their fault. If it is their fault then they are liable. The first thing they did was investigate whether their systems were compromised or not. Regardless of what they discovered, they are taking the stance that their machines were...