Coota that sounds like someone thinking anything is better than nothing when the anything doesn't achieve very much . To me it sounds like fools pretending to forge progress when the goal is actually political mileage .
The real truth is that a given trains performance overnight on the Sydney Melbourne corridor is no better now than it was 15 years ago provided it didn't catch up to anything .
About all you can say about ATMS is that it could allow a few more trains on the corridor but the average speed of the trains will be lower . The individual operators won't thank anyone for this because individually their trains will be less competitive with road freight not more .
Actually you can see this being better for ARTC because a few more trains means a few more access bucks - for a while anyway .
Time is money in the freight forwarding business so if if all gets too hard/takes to long where do you think more of the customers are going to put their freight ? Yep , on the back of a cut throat priced truck .
Like Rome the Hume wasn't built in a day and a small number of significant deviations WILL do more than any Play Station signalling system could ever hope to .
Throwing good money after bad is something the present failed Government is good at , shame its not our money and some day soon the lenders will want it back . Not to worry , it won't be the liars or the gooses problem then will it ?
I suspect that if you look at minutes saved per dollar spent, a successfully implemented
ATMS would comfortably beat your "realign and duplicate" everything on the east coast (assuming a scope for what you propose). I suspect it is competitive with many of the much smaller "deviate this, passing lane here" incremental type projects. Even if someone did stumble over a spare ten billion or so to provide the massive upgrade you seek (noting that ten billion probably only gets the approaches to Sydney sorted...), ATMS would still make that more effective - in fact - I suspect the cost of signalling that sort of upgrade over the east coast network would be more than the cost of ATMS.
You mention the theoretical maximum capacity of a line is based on the speed of the slowest train. But note that is the theoretical
maximum. If you could come down from the academic ivory tower that your train cab sits upon, then you would realise that in the real
issues (I enjoyed writing that...) mean that the actual maximum capacity of the line is less than that. The overall efficacy of the safeworking system used is one of the reasons for the gap between the theoretical maximum and the real capacity. In your "own goal" - you identified one of those practical aspects - the spacing of mid section signals. ATMS helps to address that gap. At other times there have been discussion of signal sighting issues, advance warning issues, designing signalling for the lowest common denominator (worst performing) train etc (I'm sure you've been one to complain about all of these!) - ATMS solves or helps to mitigate all of these.
I don't have time to track it down, but in one of the recent Hunter Valley capacity planning documents there was a reference to how many additional tonnes of capacity ATMS was expected to deliver (it wasn't huge - but it might have been of the order of a couple of percent increase or something). That's despite that system already having extensive line side signalling and also having relatively easy access to whatever capital it needs to fund other track improvements (because the main track users ultimately can be made to pay).
Then you have all the safety aspects on top of that. It is not hard to find recent incidents that the system would go a long way towards
Then there are the differences in systems between states (and within states) - that doesn't come without ongoing complexity and cost. Finally you have the simple reality that maintaining lots of line side infrastructure is expensive. All up it is a pretty compelling situation.
Whether your massive "duplicate and realign" project would be worth doing in the first place is really a separate issue. I think we can all be pretty confident that the sort of funding required isn't to be realistically expected within the next decade.
Finally, note I emphasised successfully implemented
. Because it is system wide, because it is safety critical, because it has a huge impact on the efficiency of the rail network and because there is signficant up-front cost, you don't want to cock this up. Hence spending some time and money to make sure that this thing works as required seems like a pretty good idea to me. While the current delay makes me rather nervous, hopefully I won't be disappointed in the long run. Just have to wait and see...