P: Auto cleaning of Make a Second Copy To

I use the "Make a Second Copy To" feature all the time.  I find it invaluable.  If I stuff up and lose an image or deleate and realise I need it some days later, it's a God send.  It's much easier to retreive recent images that way than from a full backup.  Of course the Lightroom 2nd Copy file builds up very quickly.  Every now and again I'll go into it and deleate anything more than about 2 calendar months old.  We have such good facility to clean out old previews.  Can't we have something similar for the Lightroom 2nd Copy file?