Well your 1000 networks is getting 1/1000 of the data that a single network is getting. So the dynamics are similar.
X data on SAFE will see Y farmers accepted per period.
X/1000 data on one alt network will see Y/1000 farmers accepted per period. (approximately)
So 1000 alt networks will see Y farmers accepted per period. Same as the whole SAFE network
BUT BUT BUT people using the 1000 alt networks will need a client running connecting to the many multiple networks containing the sites they want to browse. What a nightmare that will be
Remember that the network is segmented into sections so the one SAFE network will have 1000 times the sections of each of the 1000 alt networks. And each section handles the load of new people joining so basically as efficient as 1000 alt networks