We race three 40ft catamarans full tilt through the narrow channels round Brownsea Island

We beat Brian Thompson on a circumnavigation today. Thrashed him in a Lagoon 400.

OK, it was a race round Brownsea Island in Poole Harbour, and I’m not sure he didn’t give a bit away on his steed, the Fountaine Pajot Lipari 41, but our crew is claiming victory over Britain’s most decorated record holder, multihull maestro and the man who has helmed the giant 130ft Banque Populaire at 45 knots.

As I reported in my last blog, team Yachting World is doing an in depth test of 40-ish foot cruising catamarans, a size and type that has been rapidly growing in popularity for long-distance and liveaboard sailing.

Today we left our overnight anchorage off Pottery Pier, on the west side of Brownsea and headed out of the harbour. An easterly had kicked in and outside it was blowing a good 20 knots, with punchier gusts.

That meant one reef and in some cases two for our catamarans. The conservative advice of most manufacturers is to take in a reef at about 15 knots. As we were kicked around by the slabs of wind against tide we soon got to feel the peculiar motion of these boats.

Movements that would be translated into heeling in a monohull become here a slightly exaggerated corkscrew pitching, a lively and jerky movement that you can feel all the more in the elevated embrasures of their high helm positions. Designer Nigel Irens, who sailed with us today, likened the motion to riding an elephant. That is the most apt description I’ve ever heard.

After a scoot off Studland Bay we came back into the harbour and embarked on a crazy photoshoot. We made full sail and hared off round the twisting South Deep channel at the back of Furzey Island, three abreast and sometimes only a few feet apart.

It’s the sort of mad thing you sometimes get to do on boat tests and would never in a million years contemplate on your own boat. I was at the helm of the Lagoon, loving the hair-raising experience of racing what must have looked like a sextamaran careering past the line channel markers like that out of control bus in the film Speed.

I’m sure I noticed Gerry and Wendy, owners of the Lipari 41, looking a bit sweaty at what we was being asked of their new baby. With top sailor Brian Thompson nonchalantly at the wheel, what could they say? He was clearly in perfect, inch-precise control. Wasn’t he?

But if he was, how could they be sure I knew what I was doing, steering the Lagoon alongside at 7 knots, no more than a metre away?

We cut across from Brownsea to Poole at the same speed with less than 2m of water under us at times and then the competition began again as we short-tacked all the way back to the entrance. Ostensibly this was for the benefit of the photographers, but it turned into a race, as these things do.

We did beat Brian, but we in turn were beaten by the Broadblue 435, which definitely seemed to have the edge upwind.

I have to say that steering a multihull upwind is a very different experience from a monohull and that has been interesting. On a mono, you steer best on the wind judging a mixture of heel angle, helm feedback, speed and heading. All these give that feeling that we call ‘the groove’. As far as I can make out there is no such thing on these cruising multis and that can be quite disorientating.

Brian Thompson, with whom I sailed briefly in those lumpy seas this morning, tells me it’s much more about keeping boatspeed up, being careful not to pinch or wander off (all too easy with a completely neutral helm) and keeping a careful eye on heading and wind angle. I never felt sure I’d got the hang of it. I suspect that on my circumnavigation the autopilot set on apparent wind angle might well have done a better job.

I noticed that Nigel Irens said very little about the performance of these catamarans. The ace designer, who has produced some of the fastest oceanic catamarans and trimarans ever built, including Ellen MacArthur’s B&Q and Francis Joyon’s reigning round the world record holder IDEC, confessed to me that he does not like the aesthetics of these boats.

For all the huge and mainly level accommodation cruising catamarans offer, the high freeboard hulls and centre clearance over a length of 40ft does make them look very blocky and cumbersome. I think most of us would agree with him: they look rather ugly.

As for performance, the place where so many people say these boats shine, I still remain unconvinced. We were sailing upwind at over 7 knots today in over 20 knots true, and touched 9 knots downwind. That’s something well within the capabilities of a fairly average 40ft cruising monohull.

I am yet to be converted.

But at the same time I’m learning a lot, and am seeing more and more clearly why people are choosing to make long downwind passages to sunny destinations on these cruisers. There’s a lot to like as well.