If I cut off 1GB from a 2GB file 4 times for a single show (before both sets and both board and mic files) that's 4GB.
Just out of curiousity, what, or in what scenarios, are you recording that you find yourself deleting 50% of the recorded time?
Well in the above example there would probably be another couple of files that there is less to delete from so I wouldn't say 50% is standard. But sure 20-30% very often.
My scenarios vary. In some cases I work at the show. In others I shot video for the band. And sometimes I don't want to be bothered and hang with friends during the show. In each case I hit record when I get the chance.
The one specific venue where this scenario most often happens has the soundbooth on a second level and just getting through the crowd to reach it is a pain. Easier not to.
This obviously need to be a venue and type of music where you know where the levels need to be. Also I don't need to run on batteries so that is not a concern.
But pretty much at any venue with multiple sets I try to get to the recorder as a set ends. I then immediatly start recording again in case I forget (or something happens where I can't, again I sometimes work the show) to start it again at the end of the break.
And in a couple of cases I've set up at soundcheck and are not sure I will make it back for when the show starts. So I just let it record from say 4 pm or whenever the soundcheck is untill end of show. The Edirol does 18 hours of 4 channel 24/96 so not a problem. In that scenario there are usually several completly empty files.
Hope nobody objects to deleting those