(emphasis above added by oldsig127)
Mostly agree with what you say, but which entirely fails to address the point I made - is there really enough work on large naval vessels generated by the RAN to prevent the yard sitting idle in between? And how often will we need to build more than a pair - three at most - of the same design this side of 2050? Sorry, can't see it. How many have we *bought* in the last 30 years?
Assail is dead right. There's simply no economy of scale in building tankers/replenishment ships etc which even the RN can see are more sensibly built where there is such economy
oldsig
What many don't realise is ever since the final two FFGs were constructed under the Australian Frigate Project major vessels have predominantly been constructed in a modular manner at multiple locations. This permits yards to specialise on certain types of work, they can work predominately on keel blocks, blocks containing weapons systems, magazines etc. (VLS, gun hoists etc), superstructures, wave guides, control rooms, armour, or maybe just very good at producing simple blocks quickly and inexpensively.
This would permit a baseline of pretty much guaranteed work for multiple yards in multiple locations, each yard working to produce their particular blocks as efficiently as possible so as to win as many of the simpler common blocks as they can on merit. The ultimate prize would be winning consolidation and delivery work on new projects, i.e. prime contractor. There are even non shipbuilders who could conceivably bid for and win simpler blocks to keep workforces busy and productive during downturns in their regular work.
Due to modern vessels being increasingly more modular and being constructed, almost exclusively, from pre-fitted out blocks, super blocks and mega blocks it is possible to develop robust and effective processes that repeat and improve the same processes over and over again, without ever building a complete ship.
I make no secret of the fact I worked on subs destroyers and patrol boats but before that I was in automotive R&D, later years with manufacturers but initially with the components industry. What defence and specifically shipbuilding is doing is old hat in automotive, everything the vehicle assemblers don't absolutely have to do themselves they subcontract, even all design, development and engineering on some special/niche models, what they concentrate on is doing the same jobs over and over again evolving and improving processes as they go. Same with the components industry, continuous improvement and finding commonalities to permit them to apply the same improving and evolving processes to as many different products for as many different customers as possible. Exactly the same applies to ships, not entire ships, but the components that makeup the ships.
The repeatability of the processes to build ships is where savings and efficiencies can be made, the fabrication of stringers, welding of shell plate, bulkheads, decks, pipe segments, cable terminations, equipment foundations, same things over and over again. Taylor Brothers did the accommodation outfit on the AWDs, imagine flat pack cabins, specialist teams sent by them to any facility to install the kits on any ship they are contracted to do. Thanks to ANZAC ASMD and AWD (maybe FFGUP to a lesser extent) we now have a lot of local expertise integrating high end combat systems.
IMO fat ships are worth building locally because, although they could be built cheaper elsewhere, there is far more to it than sticker price. There is the usual argument of locally spent dollars remaining in the economy but there is also the fact they add to the critical mass of local capability, building simpler ships locally helps reduce the cost and amortises the investment of building complex vessels locally. Outside of shipbuilding it also supports mining, steel and construction industries in lean time and makes it cheaper to improve and build infrastructure to support and facilitate boom times.