SHE (Subtended Head End) is indeed a 'thang', and is the preferred method of roll-out in far-reaching areas where spine capacity is an issue.
It is not a straightforward fix and there's a list as long as your arm of 'criteria' to be met', before this solution (X2 solution) will be deployed. Of course, costing is top of the list .... but THP, power availability, Exchange chassis, etc ... are but a small part of the considerations.
However, simply put .... a SHE can provide feeds to 1024 premises from just 4 fibres. A massive 'assist' in the FTTP deployment plan, IMHO.