[CQ-Contest] self help during contest

[N7DF]

While most people agree that using a recording of your operation in a contest to make changes or corrections to your log after a contest is over is not acceptable practice; what is the situation if you use a recording during the contest period to review your log?  
 
In the 160 meter contest there is always the period during the day on saturday and sunday when the band is dead.  If you recorded the friday or saturday night operation you could use the recording during these periods to review your logs and correct errors.  This is inside the contest period and does not involve outside help so why should it not be permissable?
 
Since many radios and some software permit recording and playing back individual QSOs there seems to be no difference other than the time duration of the recording.
 
For that matter, why should an activity that involves only yourself not be acceptable?  In other words, why can't you record the contest operation and use your recording, after the contest is over, to check the accuracy of your log?  You are not creating new QSOs, only corrrecting ones that have already been made.