Buchanan, a giant of Australian cricket, believes beleaguered skipper Ponting, however, needs fewer duties to worry about before he can take his team back to the one-day game's summit.
Buchanan, though, pointed out they are still the world's top-ranked team in 50-over cricket and believes they will reach a fifth straight final at the Feb 19-April 2 World Cup, to be held in India, Sri Lanka and Bangladesh.
"The Ashes is finished with," Buchanan, 57, told Reuters in a phone interview from his Brisbane home, which had been spared any flooding that has ravaged much of Queensland.
"The conditions they will experience will be different; they will be facing new teams every third day, so it's now just about what is required to win the World Cup."
Cynics might suggest his exit was timely. Australia's current travails come during a transitional period as the team continues to adjust to life without a raft of now retired world-class players who came together in one golden era.
"He has been allowed to take on way too much in this so-called rebuilding phase. His principal skills are in and around the team, leading on the field and leading with the bat.
"Provided that is all he is asked to do -- and I think a World Cup will allow him to do that -- that will give him a clearer direction on what he has to do in the short term."
Buchanan had forgettable spells with English county team Middlesex and Indian Premier League franchise Kolkata, but was highly successful with Queensland and then Australia.
His intent to be at the forefront of change, sometimes using left-field theories, divided opinion.
He favoured psychology more than the baseball glove and bowling machine. Warne was a frequent critic, while ex-Australia captain Ian Chappell has rarely supported the role of a coach at elite level.
Some observers undermined Buchanan's achievements, claiming anyone could have been successful with such a talented group to work with.
"Buck", though, pointed out Warne was not part of the 2003 or 2007 World Cup wins, while McGrath was not as influential at the latter two World Cups as '99.
"I never took this position with the idea I was going to tell Warne, McGrath, Hayden, Ponting how to play cricket," Buchanan said.
"I could provide questions and an environment that would challenge them but ultimately your principal role is to make sure they are their own best coach and that they know their own games inside out."
Little has changed in his outlook on coaching in his current role as a motivational speaker, which accounts for most of his work nowadays.
"If I visit an accountancy firm I will ask them where they want to be. Do they want to be the best accounting firm in Worcestershire, or the South East of England, or the UK or Europe? Where are they going?"
Although Buchanan opts to support his three sons and two daughters in their chosen fields in his spare time now, cricket remains his passion. When asked to predict the World Cup finalists, his patriotism is clear.