From memory the whole NET v SAP issue was due to Newcastle Football wanting to push more kids through the program not just 2 teams per age group.
This led to NNSW allowing them to have 3 teams for a while but they wanted more.
Therefore they created NET to allow more teams and kids through the programs. Newcastle Football wanted more players as felt that only 2 teams per age group was not enough to fill NPL squads in u13.
I agree with this opinion. However with SAP now moving over to clubs this is increasing number of players through SAP and I am unsure why there is any need for NET.