I'd like to see someone come back home with a small TARDIS fleet and try explaining to the Chief Mechanist:
a) where these TARDISes were during the War
b) why their serial numbers are identical
c) why every single part, upgrade, manufacturing defect, and quantum black box are identical
d) why there is interdimensionsl portal tech loaded into the Console.
Seriously though: PPC tech latches onto the Console like cancer. It's really hard to get rid of. Aside from, you know, the bloody tracking devices...