What is more the Kent bowler can produce impressive character witnesses: Adam Hollioake, the England A captain, Australian Test batsman Greg Blewett and much closer to home for Atherton, his Lancashire colleague Warren Hegg, wicketkeeper on this tour.
Headley has been mystified since hearing statements attributed to England's Test captain that he lacks the ability to bowl a ball that leaves the right-hander. ``I don't know where he gets the idea, unless it was after facing me a couple of times last summer,'' Headley says. He is clearly miffed at this canard, and thinks it partly explains his failure to make his Test debut last summer and his omission from the winter senior party.
Headley was an outstanding success on the England A tour of Pakistan a year ago, as a last-minute choice, taking 27 wickets on largely unresponsive pitches, but a hip injury kept him out of Kent's attack for all but 10 championship games.
Now, after career-best match figures of 11 for 98 on the easypaced Adelaide Oval here which spearheaded England A's extraordinary 12-run win over South Australia, Headley has earned plaudits from colleagues and even grudging admiration from Australian opponents who would normally rather drink warm beer than praise a Pom.
Headley had Blewett, who is due to play for Middlesex next year, twice caught by Hegg in the match in the space of six overs with deliveries which pitched and left the opener squared up.
Blewett and Jamie Siddons, the South Australian captain, both testified to Headley's rhythm and consistency. Hollioake was in no doubt: ``Dean bowled a good pace all through and swung the ball both ways.''
Headley acknowledges that his ``in-ducker'' is his natural ball. Now nearing 27, as a fast bowler he realises he has a limited time in which to reach, and stay at, the pinnacle of the game. Yet his silky action and athletic build enable him to keep going for demanding spells. On the last day in Adelaide he bowled for 90 minutes with figures of three for 11 off 10 overs, half of them maidens.
It is the action at the moment of delivery, the left arm falling away, which some would say is Headley's only flaw. Coach Mike Gatting and manager David Grave ney have talked with him about this - but they are sensible enough not to push the matter. Memories of Devon Malcolm's fall out with Ray Illingworth in South Africa over an identical issue are still too uncom- fortably near the surface.
Headley is nothing if not a pragmatist. ``At my age I don't think it would be easy for me to change. You can't easily reshape an action now as you could with a youngster.''
He is a thinking bowler, always trying to work out an opponent's vulnerable areas. When Jason Gillespie stretched forward to drive him for a boundary as the Adelaide game reached a gripping climax, Headley pitched the ball further up, pushed him back into the crease and then sent down a shattering, swinging yorker to win the duel.
His ambition to prove Atherton wrong and make the Test team is self-evident. But this engaging, sparky personality knows that patience off the field as well as on is essential.
The England A management have given him all but the remaining two first-class games off. So he will be putting his feet up when the tourists meet the Australian Cricket Academy in Mount Gambier on Friday.