The infrastructure works involve clipping a few pallets of standalone* ETCS positioning balises to sleepers very precisely. NR managed to do this at far more stations before all the 700s** arrived for example. How does this qualify as significant? NR managed to fit the Hima-Sella Tracklink3 balises for SWT previously (e.g. for 458 Windsor line ASDO) without issue, this isn't that different.Considering significant infrastructure works would be required for the 701s to make full use of this technology and NR are struggling to maintain what they have already I have some serious doubts that forcing through their desired method of operation is going to the yield the results they are looking for..
*No external wiring /power required.
**700s use ETCS balises for ASDO and CSDE.