What has emerged is Port Otago would have been required to provide two separate payments, possibly totalling between $50 million and $70 million.
The first would be to equalise a 50-50 shareholding in the new business; the second to buy into its share in future, joint savings.
The hard question is whether the ORC, which has received almost $70 million in dividends from Port Otago during the past 22 years, would have seen sufficient benefits in the purported 50-50 partnership to sanction a merger.
The positive for Port Otago was the potential for accumulative capital expenditure and operational savings over decades of tens of millions of dollars, but that might also have meant accepting deferral of money spent at Port Chalmers - the point of difference between an attractive and unattractive port.
With giant shipping companies calling the shots on whom they visit, having 21st-century infrastructure in place is imperative - albeit hugely expensive and reflecting poorly on annual financial statements.
One industry analyst close to the proposal said "all levels" of owners and stakeholders, the public, port management and port boards would have had to embrace the concept, but the public and some senior port managers were "less than lukewarm" about the proposal.
"However it [the merger] was presented, it would have looked like a takeover by Lyttelton."
The entire merger scenario evolved from Port Otago's grabbing a contentious $37 million, 15% blocking stake in LPC in March 2006; effectively quashing a bid by LPC's majority owner the Christchurch City Council to take over, delist and sell LPC to an international port manager.
Thirty months later, Port Otago and LPC finally announced a merger proposal existed.
Initially, in order for the smaller Port Otago to take a 50-50 interest with LPC in the merged entity, it was proposed the ORC would have had to contribute between $30 million and $60 million to balance up the shareholding.
In a report later commissioned by LPC from an Auckland consultancy company, it was further suggested the ORC would have to contribute more cash in order to share in the future cost savings - suggesting the second cash contribution be more than the share buy-in figure.
This second request for cash was "hugely disappointing" to Port Otago and considered a "kick in the gut", according to some sources.
However, it appears not to have deterred Port Otago's board from persevering and the second figure was watered down to less than the share buy-in; but was still in the tens of millions.
Seemingly, even with two payments necessary, Port Otago still saw enough financial benefits in a merger to continue.
It was envisaged the head office of Port Otago would have to move to Christchurch.
It is not difficult to expect a Lyttelton-based board would favour spending money on Lyttelton wharves and channels over those at Port Chalmers, spurred by the widespread earthquake damage sustained at Lyttelton.
The deal foundered earlier this month, when the pair jointly withdrew from the two-year negotiations.
Negotiation details had been secret because LPC is a listed company and it must release through the stock exchange any details which could affect its share price.
Port Otago, tiring of repeated delays and the effects on staff and business strategies, pushed LPC for a final recommendation to he made by the end of November.
However, after Christchurch's earthquake and the substantial damage to LPC's Lyttelton assets, the LPC board wanted to postpone the deadline until the first quarter of 2011, prompting Port Otago to say "no thanks" and LPC to draft the joint statement ending discussions.
Behind the scenes, some staff at dairy giant Fonterra were expressing concerns about the merger - as were shipping companies - and the medium-term implications of having one South Island port having predominance over the other.
The hurdles for a merger success were many and high.
Port Otago's enthusiastic board may be ruing a lost opportunity, to the end believing the merger remained "conclusive and compelling", but it was unable to publicly reveal the detail or the financial gains.
Port Otago's retention of the 15% stake in LPC, which has reaped it $3.2 million in dividends, leaves it in a strong bargaining position.
The merger exercise no doubt also offered Port Otago insights into LPC's affairs.