I think it’s that he needed to write at least half a song. Not necessarily a finished song but mostly there that the final recording artist can add their own things to it.
I'm not sure you really can. Even if you could, there wouldn't seem to be much value in a partial song. I always assumed the real reason was that there was a long-term contract (say, X number of songs total over Y number of years) that was broken up into shorter periods (3 month or 6 month periods, for example), with a portion due each period, and for some reason the total number of songs wasn't evenly divisible by the number of periods, so they ended up with each period having 4.6 songs due. I'm not sure exactly how to determine whether the quota's been met each period without actually turning in .6 of a song - perhaps they give you some leeway if you turn in 4 and can show that you've started on the next one?
He said in an interview that it was a reference to collaborating with someone on a song. So he had to write .6 of the song with the other person contributing the other .4
@hawkinbj obviously, but that doesnt mean they wont. its just the risk you take with going to the concerts.- hate it too just for the record. but i just try to ignore it as best as i can