Are England an accident waiting to happen or a grand design?

Compton: England top-order lacks backbone (5:46)

Aakash Chopra and Nick Compton discuss the two-spinner strategy and overall team composition ahead of the fourth Test (5:46)

When England were at their best between 2009 and 2011 or so there was a predictability about almost every aspect of their cricket.

They had a settled batting line-up, a settled slip cordon and a settled bowling attack. Squad announcements could be cut and pasted for months at a time.

Those days are long gone. It might just prove that England have stumbled upon the perfect line-up ahead of the fourth Test in Southampton, but it feels patched together rather than engineered.

There is some justification behind the tinkering. Jonny Bairstow, for example, has a finger injury that necessitated he relinquish the gloves, while Chris Woakes has a long-standing quad issue that rendered him unfit for selection. Ben Stokes also has a knee problem that will limit the number of overs he can deliver. The knock-on effects of those injuries was bound to create ripples.

But England go into this game looking just a little vulnerable. Few of their batsmen are in their regular positions, after all, and there are four left-handers in the top seven against an attack that favours them. And, as well a new keeper and slip cordon - well, not new so much as revisited - they appear to have abandoned their continuity of selection policy. Meanwhile, their most pressing problem - the fragility of their opening partnership - has not been addressed at all.

None of that necessarily makes the selection of the side wrong. It's just that England have a side stacked with aggressive allrounders most of whom would be best placed batting at No. 6 and very few candidates to strengthen the top three. And in asking Bairstow to move up to No. 4 - an unusual response to a man breaking a finger - they are asking him to fulfil a role he has almost never attempted in county cricket and for which he expressed little enthusiasm on Tuesday.

It is not impossible he could make a go of it. He has the talent and it could even be the making of him. But if he is to make it work, he may well have to curb the natural aggressive instincts that have earned him much of the success he has enjoyed to this point. If, as is entirely possible, he comes to the crease within the first 10 overs and continues to push at the ball, he will quickly expose a middle-order that looks more exciting than reliable.

The same could be said for most of the batsmen. Joe Root wants to bat No. 4, Stokes has spent most of his career at No. 6 and it is only a few months since Ed Smith, the national selector, talked about Jos Buttler as an ideal No. 7. A few days ago, Moeen Ali scored a double-hundred against a strong Yorkshire attack while batting at No. 3. There is, for sure, some method in the madness of mixing all that up. But there may be some chaos, too.

England have altered their slip cordon, again, too. Root, whose catching gained a far from effusive review from Trevor Bayliss only a couple of weeks ago, will field at second slip with Stokes at third replacing Keaton Jennings. It said a lot for England's lack of confidence in the position that Root explained the changes not by way of suggesting they would catch better as much as they would deal with the disappointment of drops better.

"The hardest thing to get your head around in Test cricket is dealing with when you've dropped one," Root said. "It's easier to ask experienced guys who have done that a lot more to handle it better."

Ollie Pope is a particularly unfortunate victim of all the tinkering. Asked to fulfil a role that was alien to him - he bats No. 6 for Surrey but was required to bat at No. 4 for England - he has been jettisoned after just three Test innings. As a result, he could be forgiven for wondering what happened to the policy whereby a player was given "one Test too many rather than one too few" that has been touted so often in recent times.

Dom Bess (two Tests) and Jack Leach (one Test), who appear to have become England's third and fourth-choice spinners, could be forgiven similar thoughts. Perhaps Sam Curran, who was dropped a couple of Tests after producing a player of the match performance, too. You wonder whether such treatment - and the insecurity it can breed - compromises their development and confidence within the dressing room. And if it doesn't, why can't Alastair Cook, or other experienced players, be dropped when out of form? It seems, at present, as if England find it much easier to drop according to age than merit. Bess, Curran and Pope were all 20.

"That's part of international sport," Root said in explanation of the Bairstow decision. "You don't always get what you want. And hopefully he uses it in the right way to continue to work really hard at that side of his game. And he and Jos two can push each other to keep improving in that department."

There were no guarantees that Bairstow would win the gloves back, either. With every chance that his finger will not have improved sufficiently for England to make any change ahead of the final Test at The Oval, it seems Buttler will retain the job. Then, when the side travels to Sri Lanka, it will be unclear who the first choice keeper has become.

Admirably meritocratic? Or unnecessarily destabilising? We'll see. But you do wonder how many people in that dressing room are starting to look over their shoulders.

There was one nice moment at the end of training on Thursday. Once all the players had left the field, Mark Nicholas and Robin Smith - both hugely popular and significant figures in Hampshire cricket - emerged from one of the function rooms overlooking the ground and took some pictures of one another playing imaginary shots on the Test pitch. Smith has had some tough times in recent years so to see him in fine fettle and, even without a bat, unleashing that famous square-cut was heartening and reviving. How England could do with a batsman of his class now.