England embrace the 'McCullum way'
You have to be careful using phrases like "rock bottom" in regards to England cricket. Experience - bitter, painful experience - has taught us that, just when you think England have hit the bottom - such as the 5-0 Ashes defeat at the start of 2014 - they go tunnelling; the World T20 defeat to Netherlands that followed the Ashes whitewash springs to mind.
But, by any standards, the Lord's Test against India in 2014 was a low moment. It was not just that England were beaten in their own home by a team that travels with the apparent enthusiasm of an agoraphobic. It wasn't just that they were bounced out by a seamer who warrants few mentions among the list of the world's most hostile. It was that the game was overshadowed by an increasingly bitter row over an alleged altercation between James Anderson and Ravi Jadeja during the previous Test. English cricket, it seemed, was neither successful nor attractive.
England have not always been easy to love. While there have been moments even in recent times, most notably the summer of 2013, when they were successful, they have rarely been able to win over all their detractors. The words used to describe them - words such as remorseless, relentless, professional and hard - all hint at respect but not affection. They were admired, certainly. But loved? Not quite.
They also irked opponents. Opposing teams talked of England as the side they disliked most, with Sri Lanka targeting a couple of especially vocal players during the series in 2014 and India justifying their sustained campaign against Anderson with the argument that he had become "a boil that needs lancing" in world cricket. The face of England cricket was, all too often, a snarl rather than a smile.
Quite where things changed is hard to say. Anderson admitted that, post Jadeja-gate, he thought long and hard about his on-field behaviour and concluded that there was no need for the attitude that sometimes accompanied the artistry. There was talk ahead of the World Cup that England would play more positive cricket. There was talk in the Caribbean that England's approach would no longer one of "battling" but instead they would focus on "expressing skills" and "showing their talent." And there was talk after the New Zealand series about "playing with a smile".
Sometime over the last few weeks, it all came together. The influence of Peter Moores, Paul Farbrace, Andrew Strauss, Trevor Bayliss and, crucially, the example of Brendon McCullum all provoked some reflection within the England dressing room.
They accepted that their previous method had ceased to bring results and that it was not a fair illustration of who they were as young men. They reflected on the response to their success against New Zealand and found that they enjoyed the positive response from supporters. They learned from McCullum that there is no conflict between being decent and playing hard. They learned that if they played attractive cricket and behaved as attractive people, the public would respond positively.
The training trip to Spain appears to have crystallised the idea. The team - and this development is led by the team rather than instilled by the management - discussed not just how they wanted to play, but how they wanted to be perceived.
When England sides have talked of legacy in the past, it related simply to winning. Now when they do so, it relates to inspiring another generation of cricket lovers. It relates to making supporters proud not just of the play, but of the players. It relates to winnings hearts as well as minds. Winning in itself if not enough.
"There is a feel-good factor about English cricket," Alastair Cook said. "Whether we've won or lost it has been a bit of a crest of a wave. We had a brilliant one-day and Test series against new Zealand and it's carried on there. People are positive about English cricket and that's rubbed off on the players."
Time will tell if this approach will withstand the heat of battle. If it will withstand disappointment and success. But England were provoked verbally on several occasions in Cardiff and there have been times in the last few weeks when they have been put under pressure with bat and ball. On each occasion, they have come out - figuratively at least - swinging and smiling. The early evidence suggests that their conversion is genuine and permanent.
There has been much talk of new eras in England cricket of late. The Moores era, the Morgan era, the Harrison and Graves era and the Strauss era. But this time it does feel new. Whatever your views on Kevin Pietersen, his international career is now over - the success of England's young limited-overs squad in the series against New Zealand hammered a final nail in that coffin - and whatever your views on Andy Flower, Moores and Giles Clarke, their influence has now waned substantially. This team has a lot less baggage than previous incarnations.
One of the few constants is Cook. While there were few signs in the first couple of years of his captaincy career that he would develop into a particularly inspiring leader, history should have taught us to never write the man off. Just as he harnessed his talents to develop into one of England's finest Test opening batsmen, just as he has developed into a fine slip catcher, perhaps he can grow into the role of captain?
"You do get better," Cook said ahead of the second Investec Ashes Test at Lord's. "You do learn on the job. I hadn't done it for any other team. You have tough moments that you look back on and think could I have done it differently? You are constantly having to evolve."
His job for now is to ensure England play with the same focused freedom that they demonstrated in Cardiff. That does not mean looking to play safety-first cricket to attempt to protect the lead - as "old England" might have done - it means playing equally aggressive cricket with the aim of increasing it. And if there was any danger of complacency, it should have been banished by the knowledge that England have now gone one-up in their last three Test series. On the previous two occasions, they failed to hold on to the lead. There will be no getting carried away this time.
"Australia probably still are favourites," Cook said. "They only have to retain the Ashes, I suppose."
The fact remains, though, that 15 of the last 17 teams to take a lead in the Ashes have gone on to win the series. And if England catch as well as they did in Cardiff - where their fielding reached a standard it had not achieved for a long time - they will give themselves a great opportunity to repeat the success.
"We took our catches and played good cricket," Cook said. "One from one is pretty good, the challenge now is can we do it again here. The last three Test series we haven't done that.
"But I do feel we have made a big stride forward. The younger guys have more experience now but, as I said before Cardiff, there is no point looking back. If we come unstuck in this game, it is about what we can do in the next one. That's the attitude we have in our camp: we're not protecting stuff, we want to get on the front foot."
With Australia taking an equally, and more characteristic, punchy attitude, this series is brewing to be a fine advert for the game. Coming a day after the MCC world cricket committee reiterated their concerns that Test cricket, in its current format, "will not survive", that is surely something to be celebrated. England's conversion to the way of McCullum may have consequences far beyond the success or failure of one team.
George Dobell is a senior correspondent at ESPNcricinfo