I agree. We are already at 100% usage with what we already have and they aren't even in commission yet, there is no wiggle room for disaster relief, humanitarian missions, peace keeping missions, allied international deployment. If we divert the LHD from the already arranged usage structure we are actively degrading the amphibious capability from the army and putting it off.
The window that both will be avalible for deployment won't just be rare, it will be short even under the best conditions.
With no Balikpapans, no Kanimblas the only thing the army has seen of the water is off Tobruk, which is now 2 years past her use by date, busy (overworked?), and adopts the latest in amphibious operations from the 1970's (and has cost us $100 million in repair since 2007 and nearly $70m since 2012-till the end of this year). There is a lot of rebuilding to do.
We either need to abandon the idea of ARG capability (go back to Kanimbla/Choules sized ARE capability which we never really got because they were too busy), F-35B capability and timely and flexible response to humanitarian missions and cut our smaller brother nations lose and fend for themselves.
Or we get another LHD.