I have actually thrown out seeds or pods because I didn't know the parentage. I use the Dixie cups to go around and collect all the pods in (some days that's a whole lot of cups) and write the pod parent on the cup and put the pollen parent tag inside the cup. Of course I reuse the cups and I scratch through the names; sometimes I miss a few and then when I'm sorting through them the next day after writing the new name on the cup there will be 2 names on the cup
And with sometimes 50-100 cups there is no way I'm going to remember which it is unless I know it was something I would never use together; these just get tossed out.
Fred I have heard that also, "I will know the parentage when it blooms"
I dropped one of my trays of seedlings when I was transplanting them (fell upside down) and tags and seedlings went everywhere. These were some really good crosses I hated to lose, but I tossed them out because I really had no way to tell what tag went where.