The money spent on electrification was spent well in my opinion, electrification in itself is a positive move towards bringing it into the 20th century even if speeds are not improved. The global supply of equipment for diesel multiple units will start to dry up in the near future as all the major markets (Europe and North America) will be imposing the Tier 4 emission standards at the start of next year, and to date the only compliant multiple unit packages produced either require a raised floor in the centre (possibly in breach of DDA?) or a full-height engine room stealing space from the passenger saloon. Better to start going electric now so that the reliance on diesel units can be reduced and their service life extended until better Tier 4 packages are produced or electrification is extended.
The decision to spend a bit more on getting a genuinely robust overhead setup was also a good one in my opinion. To date we've only had one overhead-related problem (lines were brought down by a train near Noarlunga) where a line with electrification done on the cheap could reliably expect then every few weeks.
I'd give the A-City units themselves a C– grade, maybe a C at best. The air conditioning is ridiculously loud (possibly in breach of DDA?), the ride is terrible and the build quality of the interior feels very cheap - the plastic panels flex and rattle already, I imagine they'll need a mid-life refurb in 4-5 years (just after the last of the fleet finally get delivered) to refit with a well-built interior. I would hesitate to call them "world standard" because I've been on a Siemens Desiro in the UK - they are quieter, ride nicely and feel well-built across the board.
The real problems are the track rebuild and the signalling.
- It's no coincidence that the only bit of the route with a nice ride is also the only bit with slab track - the underpass at Goodwood.
- If the A-City units go any faster than 50-60 km/h they are subject to violent pitching movements on certain segments of track where the DEMUs absorb the movement reasonably well. The track between Mile End and Showgrounds is the worst part of the whole route, correct me if I'm wrong but I believe this section wasn't fully rebuilt with only the turnouts getting replaced.
- The signalling is a complete mess. The budgeted $105 million (who knows what it blew out to in the end?) should have got us a proper in-cab signalling system like ETCS Level 2 with no need for lineside colour light signals outside of the approaches to Adelaide. Instead, all that money got us was a load of unnecessary axle counters (business class flights for a study trip to find out how electrification and track circuits coexist in Europe would have been cheaper), all the same block lengths as before (i.e. no increase in capacity, the system can't deliver any more trains/hour in the peak than the old system did) and reduced speeds to deal with poor sighting (which wouldn't happen with an in-cab system, there would be no obstructions between a driver and their desk display or HUD).
- The lack of additional crossovers being built during the project to increase the system's resilience to failures and allow for preventative maintenance to be done on one track over the weekends while trains run on the other - I believe these were originally planned but cut to allow more cash to go into Turbo Tom's construction mates' pockets. At this point the only form of degraded working possible is bustitution.
Overall I'd give the project a D– grade, and it is entirely appropriate that Rod Hook and Emma Thomas were fired for their poor management. There should be a Royal Commission into the raft of badly managed DPTI projects (rail, the Southern Expressway and the cost blowouts at Adelaide Oval) with a view to finding out where the missing millions went.