But was their best good enough?
The commission's own question lines suggest strong concerns over how Knowles and Whittall tackled the disaster response phase, particularly Knowles' role as head of that operation.
I doubt that commissioner Stewart Bell will face any ministerial opprobrium for expressing surprise at the police refusal to transfer incident control away from Knowles to local mining experts. As Bell asked this week, "How much time was wasted ... training police officers ... in mining matters when you could have had someone there from the word go that understood the terminology?"
But in the days after the explosion, sensibilities were fragile.
When Australian journalist Ean Higgins asked, "Why is a local country cop leading the rescue operation?", Energy Minister Gerry Brownlee labelled him a tosspot and complained to his bosses.
Higgins' question could have been put more delicately, but the hard-bitten Australian journalist comes from a country which not only insists on much higher safety standards in its bustling mining sector, but also has the capability to deal professionally with disasters.
Much of the harrowing evidence that has so far been given in this inquiry suggests there would have been little, if any, chance of getting any of the miners out alive, even if rescuers had been allowed to go straight into the mine before gas levels built up again.
The mine's safety equipment was either missing or not up to scratch and there was no easy alternative way out of the mine. One expert said that by failing to promptly seal the mine, the opportunity to even recover the 29 bodies and retrieve evidence about the first explosion was lost.
Knowles was out of his depth - but what about the mining company boss?
Whittall still plays over in his head the fact that five days after the explosion, he inadvertently raised families' hopes that a rescue operation would be mounted, instead of telling them outright that a second explosion that day meant the 29 miners were clearly dead.
Sonia Rockhouse, who lost her 21-year-old "baby boy" Ben, recounted how Whittall had told the families gas levels were down and a rescue would be mounted. "He then said, in almost the same breath, there had been a second blast and no one had survived."
No wonder the families feel they were the victims of false expectations.
The royal commission is now in phase two of an inquiry that is due to report by March 31 next year.
But in the wake of this week's revelations, there are some burning questions the Panckhurst inquiry must surely address.
First, why did the Pike River directors allow Whittall to continue to front the mine disaster when it must surely have been obvious his judgment had become compromised by a combination of excessive optimism and exhaustion?
Second - and this is the more fundamental question - what responsibility did the Pike River directors have for ensuring the coal mine's safety standards were up to scratch and were implemented?
On November 24, I wrote that after five days of Whittall being the company's public face, it was surely time for Pike River chairman John Dow to step up to the plate in a show of solidarity to give his exhausted chief executive a rest. Dow did finally emerge that day at Whittall's side.
But judging by evidence given to the inquiry this week, the Pike River chief executive's judgment was already significantly impaired.
And he was so far out of the loop that it was the Prime Minister, rather than the rescue authorities, who advised him to stop talking about "heating" inside the mine and start talking about fire.
The Pike River Coal directors may have felt it was in the interests of the company to leave Whittall as the public face of the disaster. But in the interests of natural justice, they should also take the stand.
