default to LAST prehit retract values

When measuring in a channel on flexible rings 

I need to adjust the prehit retract values to get a good hit to analyze the data.

I do this in the edit window I type

 prehit and TAB it auto fills the 2.54 value            :(  

What would be useful is the 

ACTUAL LIVE VALUE at that point in the program so I know to go bigger or smaller than what I currently have. 

it may have hit either wall and bounced off ...  so it starts a trial and error routine and is time consuming.