Simtrain, just stop making stuff up.
You have no EVIDENCE, thats the problem
I am going to engage in a little speculation of my own.
There is absolutely no need or benefit at all in dual mode on the new fleet for it's currently stated use.
That said, I've always thought we were a cracked frame away from full bustitution. When this thread started more than 10 years ago, the XPT fleet was already life expired. They have had a hard life, done more Ks than any of the design engineers ever envisaged. Metals fatigues, and eventually something will fail.
As I understand the timetable for the XPT replacement project, we are still a minimum of 4 years away from a serviceable train, probably 5 for enough to replace the original 1981 fleet. This is because they need the Dubbo plant, planned, approved and eventually built before the can do much toward actually building the trains. That's not allowing for any significant delays in the project - which of course never happen in NSW - or any stuffups in the specification.
I think the chances are very good the entire fleet will be grounded more or less permanently, or perhaps just the 1980s units (15 of the 19 power cars) before the new trains come online. After a few years of bustitution, there won't be the demand for services there is now, so when the new fleet comes online, only 4 or so sets will be needed for a train each way each day.
That will leave the bulk of the new fleet available for "new" services like direct Nowra to Sydney (for which 10 car NIFs would be overkill), a route for which a dual mode vehicle would be perfect.
Or, the entire new fleet project could be scaled back to "match demand" once cost over-runs or delays are encountered.
Whatever happens, there is a lot of downside risk to passenger rail services, and not a lot of upside as the project - at best - is designed to emulate the 1990s "reformed" service.
While we all have our thoughts and speculations as to what is going to happen, and while I possibly only travel on the X a couple of times a year, I do see them regularly come into Maitland along with the NW XPL. The later seems to have had some increases in patronage but is often hampered by a lot of line shutdowns, over the past couple of months there has been 5 day 24 hour shut downs to Narrabri and on the Ulan line, with only commuter trains between Telerah & Wickham running in peak times, at these times they are disincentives for passengers and commuters alike.
The NCL services seem to have pretty good numbers on board, the bustitution of Grafton services and the buses not servicing guite a few stations, has some impact, and caused a bit of angst, but its an unknown as to how much, for many the likely faster trip without the calling in to the by stations may be an advantage.
Depending on how long it takes to get the replacement pins into the fleet of power cars means that basing anything on the future is not going to provide any real idea of patronage into the future for anyone, gunzels, governments or anyone, who knows how far the new trains will eventually go?
The one big thing though is the aspect of governments and the political whims of them, NSW is currently Coalition based on 4 year terms, QLD & Vic are currently Labour states but for how long? QLD politics is all but impossible to read as the current mob may not get another term but it has little affect on our train system outside of dumb times the XPT runs into Roma St. Victoria seems to be spending up well on PT, so Labour could stay in, I have no idea on that though.
The big fish in it all is and will be the voters, and more especially the rural voters and/or those who use PT for their visits and other businesses, there has been backlashes over the cutting of services in the past and its backfired on the government, the DUBBO venture while its a bit dumb in my thinking is a blatant example of the way that government spend up to boost their electoral prospects of re-election. The Nationals lost out that way previously now they are back owing to the Dubbo centre. I still believe Meeks Road will also be doing their far share of servicing though.
As for the Melbourne services, if they are cut, and turned back at Albury, seriously they may as well cut back to Wagga as who will be on the train between those two stations. Also there will be political issues both sides of the border. The Vic government will cop a big backlash against them if allowed. Don't forget the X currently stops at Seymore IIRC, (excuse spelling if wrong)
While I doubt the new trains will see cuts to the interstate services, I would not be surprised if it does happen.