I didn't think Alinghi would win Valencia Louis Vuitton Act 13. While the challengers would be racing hard for bonus points to take forward into the Louis Vuitton Cup, it seemed the Defender would want to play its cards closer to the chest. Alinghi proved me wrong, however, as four wins from seven races suggest sandbagging was not on the Defender's agenda after all. Fair play to Brad Butterworth and his crew, I think they gave a pretty honest account of themselves in Act 13, and they gave plenty for the challengers to think about too.

For this Act, Butterworth put Ed Baird on as helmsman, and by Baird's admission he didn't make a great job of the starts, looking shaky on his time-on-distance judgement. Butterworth didn't sound greatly impressed either. "We've had some shockers, we've been starting badly," he said. "Mind you they were fleet race starts. I think we had two out of seven that were good starts, but the rest were really bad. We've got to work on starts, particularly on our match race starts." It's hard to know if Baird's performance improved or reduced his chances of helming for Alinghi in the America's Cup Match. Alternative choice Peter Holmberg certainly isn't out of the picture quite yet.

In some races, a bad start was a blessing in disguise. In the first race, for example, Alinghi broke the line early and had to round the committee boat to restart more than 30 seconds behind the fleet. Meanwhile +39 Challenge had made a mediocre start and soon tacked off underneath the fleet in search of clear air to the right. Alinghi followed in +39's wake and when both teams hooked into new, stronger breeze emanating from a dark raincloud that was developing over that side of the course, +39 rounded the windward mark in the lead with Alinghi already up to 4th.

Race 1 proved to be a game of Snakes & Ladders from start to finish, much to the anguish of +39. Iain Percy's underpractised and underfunded crew looked set for a fairy-tale start to Act 13 as they led around every mark of the course, only for the wind to go AWOL on the final few hundred metres to the finish. As Percy sailed into a windless hole, BMW Oracle tried their luck out to the left of the course, and sailed from 7th to 1st, winning the race comfortably as their rivals wallowed helplessly in no wind. +39 Challenge was dropped from 1st to 10th.

Alinghi, having mucked up the start, also had a moment leading the fleet down the final run until they too became stranded. But they did at least salvage a 4th place from the race. The Swiss team showed a capacity to dominate proceedings when things were going their way and, even when luck was against them, still managed to grind out some sort of useful result. None of the challengers displayed that type of consistency. Initially BMW Oracle looked the equal of Alinghi, but they faltered with some uncharacteristic crew handling errors later in the regatta. Emirates Team New Zealand and Luna Rossa, on the other hand, started slowly but came on strong in the bigger breezes of the later races.

While these teams have been seen as the ‘Big Four', everyone agrees that the gap between the top teams and the rest has closed significantly since last season. Now that each team is using a Version 5 boat, the difference between the ‘haves' and the ‘have-nots' is vastly reduced. Indeed the immensely improved Mascalzone Latino - Capitalia Team grabbed a podium position in Act 13, taking 3rd place behind Alinghi and the Kiwis, and beating Luna Rossa and BMW Oracle to the punch. Desafio Espanol 2007 was another team that has stepped up a gear, finishing just 2 points behind BMW Oracle, so perhaps Paul Cayard's brief period as a technical consultant has paid off.

Possibly more significant is that both Mascalzone and Desafio have built two Version 5 boats compared with all the other ‘B' division teams who have made do with just one. Having two boats makes it much easier to develop your boatspeed. On the other hand, it wasn't boatspeed that some of the other mid-fleeters such as Shosholoza, Areva Challenge and Victory Challenge were lacking - so much as basic sailing skills. Victory in particular looked very shaky in some straightforward sail-handling manoeuvres, trawling or breaking spinnakers on a number of occasions. These are errors that at this level just shouldn't be happening, and it is all the more surprising for the Swedes to be making these mistakes when they had just returned from some hard boathandling training in Dubai a few weeks earlier. Needless to say they were impatient for the fleet racing to finish and for the match racing to begin, although it could be argued that your boathandling needs to be even slicker for the one-on-one duels.

Although the final Act last season was No.12, the organisers had originally labelled this regatta as Act 14, choosing to forego the unlucky 13. How +39 Challenge must have been wishing the original superstition had prevailed, when their brand new mast came down in Race 3 - through no fault of their own. This has been the most stop-start campaign of all the Cup teams, with British skipper Iain Percy and his merry men waging an ongoing battle with the team's management to get paid. This was the team that was least equipped to deal with such a major setback.

With pay a few months in arrears, Percy and the sailing team were threatening not to compete in Act 13, one of their few remaining bargaining chips. Whether or not some financial resolution was agreed is not clear, but with just 48 hours to the start of racing, the team was making a belated effort to get ready for competition. The new Version 5 mast was stepped in the new hull, ITA 85, for the first time. The crew went out for a test sail in the dark, returned at midnight, leaving the shore crew to have the mast ready for the first race the following day.

Fortunately the wind was light for Race 1, and +39 nearly sailed to that famous victory we mentioned earlier, until the wind went pear-shaped. The following day, after a 7th place in Race 2, +39 was lying in 5th in the early stages of Race 3, as Percy steered the boat toward the windward mark on the starboard layline. A lot of boats were coming in from the left, including United Internet Team Germany, who had to pull off a big bear-away at the last moment. It was too little too late from the Germans on port tack, whose rig clashed with +39's and brought the brand new mast tumbling down.

Iain Percy and tactician Ian Walker were lucky to get away unscathed as the rig crashed down around their ears, and a piece of rod rigging struck the deck just yards from where they were standing, passing through the carbon structure as if it were paper. As the carbon dust settled, Percy's thoughts turned from survival towards considering the immediate future of the campaign. With no spare Version 5 mast, they were facing the prospect of having to resort to their Version 4 rig, at least 70kg heavier and not nearly as powerful. Without hesitation, the German team offered the use of a spare Version 5 mast, but this would require a change to the Challenger Protocol, and the Germans' generous offer was vetoed by other challenger teams. In the short term, it looks as though +39 will be forced to use its own Version 4 rig for Robin Robin 1 while it waits for the broken Version 5 mast to be stuck back together in time for Round Robin 2.

Whilst unfortunate for the Italian team, +39's mast breakage was the most dramatic among many exciting moments during the fleet racing of Act 13. As one tactician commented anonymously: "You'd have to get through at least 10 match races to even come close to equalling the thrill of one of these fleet races." Let's hope he's proven wrong, but that comment certainly echoes a widely-held belief that fleet racing is more fun than match racing - more fun to do, more fun to watch. The question is how to make fleet racing a more meaningful part of the America's Cup. On the other hand, if the next two months of match racing can provide even half the thrills and spills we witnessed in Act 13, then we're in for a riproaring event.