i think we all knew Robin Van Persie offered plenty of flair on the pitch.

A dramatic turn of phrase off it – like the one he came out with on Friday at his Old Trafford unveiling – was rather more unexpected. Speaking of his decision to swap Arsenal for Manchester United in a £24 million deal, he said "It was based on a lot of things, and all those things went to United. When you have to make a hard decision in your life, I always listen to the little boy inside me. What does he want? That little boy was screaming for United."

Cue revelations that Van Persie was a closet United fan during the eight years he spent at Arsenal, with some suggesting his support for the club dates back to Eric Cantona.

You're tempted to be cynical about it, until you realise that Van Persie could probably have earned more than the £200,000 a week over four years he'll make at United. Juventus put a more lucrative deal on the table and, had he held out for Manchester City, he probably could have forced something through which would also have been more financially profitable.

Of course, Juve were only willing to deal on the cheap: their valuation never went past half of United's £24m. And City had to sell first, which meant finding homes for the likes of Emmanuel Adebayor, Roque Santa Cruz and probably Edin Dzeko too. A tall order, given their respective pay packets, and one which left Van Persie's future uncertain. The possibility of finding himself at the Emirates past deadline day was very real.

And so United were the fast and – relatively – simple option. His move there allows Van Persie to start the season with a new club. It enables Sir Alex Ferguson to get the man he wanted without making him the club's highest-paid player, which, for reasons of internal stability (that prize still belongs to Wayne Rooney), is important. And Arsenal end up with £24 million in the bank instead of a big fat zero in 10 months' time.

In the circumstances, it's not a bad bit of business. Especially since Arsene Wenger – unlike last year when he hung on to Gael Clichy, Samir Nasri and Cesc Fabregas until the last possible minute, leaving himself no option but to scramble for replacements of the Andre Santos, Mikel Arteta and Yossi Benayoun variety – planned his summer signings as if Van Persie was already gone

Lukas Podolski, Olivier Giroud and Santi Cazorla came in early and with the obvious brief of replacing the Dutchman in terms of both goals, presence and creativity.

Maybe that's why the mood among Arsenal fans in the last few days hasn't been as despairing and negative as it might have. This was the kind of break-up that was a long time coming, everyone was as prepared as they could be. And, football-wise, Arsenal might actually benefit from not being as Van Persie-centric as last season.

Meanwhile, Sir Alex was positively beaming. Which is rather unlike him, but then his whole modus operandi has been different of late. In the past 12 years, only twice has he bought a veteran. One was Dimitar Berbatov, who was 27 when he signed from Tottenham.

The other was Edwin Van der Sar, who was 34 when he arrived from Fulham. Of course, Van der Sar is a goalkeeper and, at just over £2m was a bargain. The best comparison is the Bulgarian who cost £30.7m and, even then, there are differences, such as the fact that Van Persie is two years older.

Was Berba worth it? His supporters would argue that he was the Premier League's top goalscorer in 2010-11 and that the club has won two league titles since his arrival. But that argument is probably less convincing than that of his detractors. Fifty-six goals in 149 appearances in all competitions is not the kind of return you'd expect. Nor would you expect him to be on the bench or in the stands as often as he has been.

Evidently Sir Alex sees Van Persie as different. And he has a case. But even then it was surprising to hear him talk of this being United's best strikeforce since 1999, when they won the Treble. Not because the quartet of Van Persie, Rooney, Danny Welbeck and Javier Hernandez aren't superior to Dwight Yorke, Andy Cole, Teddy Sheringham and Ole Gunnar Solskjaer. On a one-to-one basis they may well be. But it's remarkable for two reasons.

Firstly, Yorke and Cole had a clear-cut partnership that worked extremely well. Rooney and Van Persie right now, as a partnership, is just an idea. Nobody has established if they have any chemistry, or if they can work as a duo or a "one in front, one behind" tandem.

Secondly, it's extremely rare to hear managers compare players from different eras, let alone guys who have yet to kick a ball for them. All it does is ratchet up the press coverage and, should things fail to work out, set you up for ridicule.

Then again, this is Sir Alex we're talking about, with his ability to change and evolve. Maybe this is another chapter in that process. Maybe he feels it's time to do things differently. He's been right before you know...

Van Persie's arrival was enough to make Roberto Mancini say United are now favourites for the title. Maybe it was managerspeak, maybe he really believes it. Or maybe he was just showing his frustration once again that, with the league under way, Man City's total transfer haul consists of one guy, Jack Rodwell.

The latest name to be linked is Daniele de Rossi. He could stiffen the midfield and slot into a back three if, as seems to be the case, Mancini is leaning in that direction. The problem is he is on huge wages and Roma have made it clear they'd only consider a "monstrous" offer. And "monstrous" for a 29-year-old of his calibre with a long-term contract starts at £30m to £35m.

That is a lot when you consider he'd be unlikely to have any resale value. In February, De Rossi signed a new deal equivalent to around £9m a season, or £180,000 a week. De Rossi, understandably, is not going to leave the club where he has played for his entire career without a hefty bump. And that would take him well past the £200,000 a week mark, right up into Yaya Toure and Carlos Tevez territory – exactly where City do NOT want to be.