The email from Mark Arbib, the former Labor power broker turned wingman to Mr Packer, reveals the extent to which the Barangaroo Delivery Authority attempted to accommodate Crown's concerns that buildings proposed for Central Barangaroo would impinge on privacy and views from its $2 billion waterfront tower.

Mr Arbib's update to Mr Packer on the negotiations was tendered in the NSW Supreme Court, where Crown and infrastructure giant Lendlease are locked in a costly battle with the state government in a bid to preserve "sight lines" from their developments to the Sydney Opera House and Harbour Bridge.

"Hi mate, this is where it is up to," Mr Arbib wrote to Mr Packer in the email, containing the BDA's latest proposal to Crown, in November 2017.

Mr Arbib wrote in the email, titled "Barangaroo sight lines", that the authority had reduced the height of the tower proposed for Central Barangaroo and shifted the building's position.

"This helps restore our Opera House views," Mr Arbib wrote. "They have also re-oriented the tower, to help with views and also reduce any privacy issues for our hotel rooms and apartments.

"Now that the BDA has addressed these concerns, [Crown's development chief Todd Nisbet] is now saying the building will block some city (building) views from the apartments.

"All the apartments will have spectacular views of the Harbour Bridge and Opera House."

Mr Arbib wrote that the BDA had also slashed the height of a separate building that would have blocked views from hotel rooms in Crown's 71-storey complex, reducing "the sight line impact on our hotel to around 20 rooms".

Crown would lose some views of the Harbour Bridge from the gym and boardroom planned for levels four and five of the building's podium, he wrote.

"As you know we never had much of a view of the bridge from the podium, but we should go back to the BDA and try to improve it as much as possible."

Mr Arbib told Mr Packer that Crown's executive chairman, John Alexander, and development chief, Todd Nisbet, "haven't budged since the BDA offer and working on legal strategy with Lendlease".

"The next meeting of our internal Crown Sydney team to resolve our position is tomorrow," he wrote.

Crown ultimately rejected that proposal and negotiations between the companies and the BDA continued, even after the two parties launched litigation against the state government in August.

"That's an internal frank assessment that seems to suggest the impact is not so large," the BDA's barrister Tony Bannon, SC, said of Mr Arbib's email in his closing submissions on Wednesday.

He said the email suggested Mr Alexander and Mr Nisbet had been "a little bit more difficult" during the negotiations and thought Crown should "go back and squeeze a little bit more" from the BDA.

Crown and Lendlease are arguing that clauses in their 2015 development contracts stipulated they should have been progressively consulted on the plans for a mixed-use site at Central Barangaroo.

The companies say the BDA had to negotiate in good faith with them about proposed departures from the plan for the precinct that guaranteed them uninterrupted harbour views.

But the BDA argues the companies were only entitled to good faith negotiations and it did not guarantee their "sight lines" would be retained.

Lendlease barrister Andrew Bell, SC, argued that the authority had not explored other ways of optimising development at the site "which did not involve an impairment of the sight lines".

Dr Bell said that "one could have more area underground", prompting Justice Robert McDougall to comment: "Troglodytic race of office workers?"

Crown's barrister Neil Young, QC, argued the authority had not engaged in ongoing discussions about the proposed development for the site.

"In a sense, one doesn't even need to get to the good faith negotiations. The authority has point-blank refused to carry out important aspects of its contractual obligations."

Mr Bannon said the relevant clause in the companies' contracts recognised they would have "competing obligations".

The hearing is expected to finish this week.