Large can of worms opened here…!
The pros/cons of CPOs aside, Network Rail are not really interested in buying up more land - they are actively trying to sell off land at the moment. More land means more liability for trees, structures, earthworks - all things that could have a negative affect on their ability to run a successful railway.
The main issue, at least in my mind, is not the lack of wires up the Fife coast but the large amount of line speed changes. I’d much rather NR spend time and money on improving that aspect of the route to improve journey times and timetable resilience!
Selling off land is all well and good until you need more land again to fix a problem. E.g. for those linespeed improvements, you may want to realign the railway. It happened at Market Harborough but I believe this was only possible because there was a good amount of empty brownfield land in railway ownership.
Bridges are another big problem. You can minimise impact on locals by building a replacement bridge, but there's not often a lot of suitable free land anywhere near. The bridge over the GWML at Steventon is a great example. The lack of good alternative roads means the option isn't available to the railway to just close the bridge to traffic while it is rebuilt. The only crossings nearby are level crossings and it wouldn't be acceptable to use them for more traffic. The existing bridge is in a poor condition with permanent traffic lights, meaning it doesn't suit the locals at all.
A totally financially viable option if NR had unlimited CPO and development rights would be replace the level crossings nearby with a new bridge. This would require a realignment of the road network, and the loss of some existing houses in order to make up the connections. The funds for this new bridge could be generated by developing the land south of the railway for housing, expanding the village. There's a huge shortage of housing in the south east of England, so this new housing could be very profitable. Using the opportunity to widen the GWML to four tracks here (the bridge a current bottleneck) could deliver benefits across a pretty large area of England.
Yes, it means CPOing some houses and overturning some green belt development restrictions. But if we don't occasionally do that, we are stuck with a bridge that can't be fixed that prevents national infrastructure from working properly. It's just silly. If NR owned the land then it'd probably have been fixed a long time ago, because it wouldn't require all of this paperwork and bureaucracy to fix.
If we're not willing to CPO more often then the rational course of action is for NR to retain ownership of more land. The more lineside neighbours who are actually tenants of NR, the easier it is to deal with problems. If NR owned the houses here, then it could just evict with a plan to demolish the house. The residents wouldn't have any special right to stay at all. It's only owner occupiers we end up caring about; tenants don't have any expectations they'll be able to live somewhere forever.
