When we last left the team they were a hair's breadth away from ascertaining whether the cannon recovered from the Alderney wreck were part of a set.
And with the results of an x-ray to determine their diameters and markings proving inconclusive, the de-concretion process would be crucial in giving excavation leader Mensun Bound and conservation expert Ian Panter the proof they needed.
So the good news is that the de-concretion, where the team at the Tower of London has for the last two weeks toiled to remove the 400 years worth of detritus built up on the cannon, has been deemed a complete success.
And Mensun and his team are now as sure as they could be that the two cannon raised from the sea bed in June, as well as the first cannon brought to the surface during the first excavation mission in 1992, form part of a set, and so are evidence of a co-ordinated naval weapons system.
Says Mensun: "We're dealing with the unknown here, and that's what makes it so exciting for me. If they were from 100 years later, they wouldn't be able to show us anything that we didn't already know.
"But the fact that they are near identical in size and calibre points to the fact that they are part of the same set. And without sounding trite, that means we're looking at what, in naval terms, could be called the very first weapons of mass destruction."
The significance of the team's findings has not been lost on the guardians of the Tower, where the Elizabeth had been docked five centuries ago. Yeaman Warder Dave Phillips was the first person to see the top side of the barrel of the cannon when the team removed the final layer.
"It's been nice seeing the cannon being slowly revealed from 400 years of corrosion," says Dave. "And it amazes me that I was the first person to see its surface in living memory."
The third cannon also proved to be something of a treasure trove. The crust around the cast iron cannon, formed by the salt water acting as an electrolyte and drawing soluble iron chlorides away from the surface of the gun leaving behind the concretion layer, had not only helped to preserve the carriage but had also trapped artefacts including a musket, helmet and shoe.
And with this stage of the process complete the musket and helmet will now accompany the two cannon to York, where they will be de-concreted while the experts work on creating replicas of the guns to fire at the Ministry of Defence weapons testing site.
In the meantime the team also has a mystery to solve. The third cannon had markings on it which, once verified, may well prove to be their most exciting discovery yet. Watch this space...
Published: July 2008