Okay, try this: grab a cricket ball, or if not a tennis ball, orange, apple or something like that. Space your index, middle and ring fingers across the widest part of its circumference so it fits snugly between them. Hold your arm up straight and look down an imaginary wicket. Rotate your wrist until the back of your hand is facing down the pitch and you can look up at your palm. Try and flick the ball from your fingers as if twisting a doorknob in a clockwise direction. Now imagine doing it all at speed as your arm swings up to the perpendicular as part of a bowling action.
This is the contortion required to produce the doosra, genius invention of Saqlain Mustaq. To deliver it accurately down the cut strip to an international batsman takes skill available only to the very few. Because the wrist is weakened by its rotation, the power to propel the ball at sufficient speed must come from the shoulder and the elbow. The rules allow a fifteen percent flexion to help.
Almost every bowler who has used the doosra has had problems with their action at some point: Shoaib Malik, Harbhajan, Murali, Botha, Ajmal. And almost every bowler who has used it has been thrilling to watch, and has contributed richly to the game. In Dubai, as Saeed Ajmal ran through England with some non-spinning spinners in an act of beauty, smoke and illusion, battle raged once more.
TV evidence was damning, especially in the heightened artificiality of super slo-mo. On Twitter, opinion polarised and there were two views: either Ajmal was chucking some deliveries, or anyone who thought Ajmal was chucking some deliveries was uptight, square, boring, had sour grapes. Both sides had cause for righteous indignation.
Yet there's no reason for the positions to be mutually exclusive. Even the hardline chuckers would not want to see Ajmal's artful brilliance removed from the game [well, Ian Bell might], and equally those being dismissive would not enjoy an unregulated free-for-all in which anyone can deliver the ball however they like.
The current laws have removed the stinging, career-ending public shame that once came with the accusation of throwing. Science has shown that human beings cannot, in fact, deliver a ball with an entirely straight arm, and the 15 degree rule reflects that.
What the tests can't do is make allowances for the nature of being human; the stress, tension, excitement and fear of executing fine motor skills under extreme pressure. Ajmal probably did exceed the limits on a couple of occasions - that's not an egregious sin. But neither was he trying to cheat.
Actions can change and deteriorate over time in the same way that a batsman's technique can alter and warp. There would be nothing wrong with calling in those who bowl that kind of spin every couple of years and testing their degree of flex, rather than waiting for the umpires to report them and becoming indignant over whether they do or whether they don't. That way, all of the rancor and whispers could stop.
Ultimately, spin bowling is about deception. On a first day wicket that wasn't really turning, Ajmal played with minds. The ball fizzed from his wrist with a scrambled seam, and it had done half of its work before it even pitched. That was his true victory, and we wouldn't want it lost to rumour, spite, television replays or anything else.
NB: Yes, spin freaks, there is another doosra method with the hand facing forward. This is not about that.