Okay, let me have a go at this ;-)
First, I think that the length of the boat is more relevant than the shape of the keel or how many hulls the boat has. Second, I think we're talking a bit about comfort here because at under 50 knots the wind should not lead to serious problems for either mono / multi.
About the length of the boat: we are 64' and my estimated guess is that our sailing experience with 50 knots is equal to that on a 32' boat with 30-35 knots. At 35 knots we have a smooth ride much like a 32' boat with 15 knots.
I hear everyone thinking two things: 1) it's the waves and indeed but apart from swell from distant storms etc. the waves are related to the wind and 2) here he goes again with his 64' boat but really, I have spend much more time on a 30 footer than on our current
When we "buddy-boat" we always try to do that with a cat because they are faster and it's easier for us to match speed with them (because we're always bigger). But when we sailed together with another (smaller) mono we always see this difference in boat length. The difference is so big that we sometimes feel like we're cheating.
The same difference is also found when you reef. I mean that on a big boat, putting in a reef makes more difference in comfort level than it does on a small boat. I strongly feel that a pilot house is like an extra reef because it provides another jump in comfort and safety
compared to being out there in the cockpit
Now the difference between mono and multi. Both have a problem for comfort: the mono heels and the multi (I mean a cat really because a tri is like in between) bounces more and that includes these sideways jerks. You get used to both but once you are used to one, you start to dislike the other more. Both lead to injuries too: the OP relates of bruises caused by a knock down (I always though that meant spreaders in the water
but I guess we mean a sudden increase in heel during a gust here). A friend of ours on a cat fell because of one of those sudden jerks and landed with his back on a winch
which could have put him in a wheelchair so there's the example for the other side.
it's the same really. Mono's often sail back and forth behind their anchor
while cats don't. But cats still have that jerking motion like when a wake from another boat passes by and I need to grab my drink to prevent spilling it more often on an anchored cat than on an anchored mono. Also, not all mono's sail behind their anchors plus there are ways to stop others from doing that (riding sail). But some mono's are just terrible at this and I wouldn't consider those designs because of that.
The only other thing I notice is that tendency of a cat to bury their bows in following seas. I know they are not about to pitch-pole but I always get that nasty feeling in my stomach when it happens or even if I see it happen on another cat. This is much more a problem for small cats just like it is for mono's but it's much worse with cats compared to mono's.
When you go above 50 knots of wind it all changes but that's not the subject of this thread. I just want to write that I think the chance of some catastrophic failure on a cat is much higher than on a mono because there is much more stress.
I like posting
photo's and was just told that I don't do that enough so here we go ;-) The first one I took of Gecko, a 30 footish cat during our passage
to the Colombian coast. This means high winds and seas, we had about 30-35 knots of winds and 8-10' seas here:
The crew doesn't look worried at all but I had that feeling in my stomach already ;-) Actually, Ian had it too which is the reason he reefed his mainsail
down all the way.
The next one is us at the same place and the same time. You can actually see me taking the photo's of Gecko:
You can see that we lift
the stern from the water but the bow shows no tendency to dig in. This is the combined effect of both being a mono and being longer. Also, note we are under full working sails
Next two are on top of a wave:
And behind a wave:
We're behind a big one here and look like a submarine sailboat ;-)
And just for fun, this is later that day when we were arriving at Islas Los Monjes just off the coast of Colombia
(but actually belonging to Venezuela). We have just furled the jib
and gybed to go between two islands (they are more like rocks really). The photo
was taken by another cruiser who climbed the rock and had his portable VHF
with him. The wind were up to 40 knots now and even without the jib
we were planing at well over hull speed
(the wake looks like we were doing 14 knots).
You can click on any of these photo's to go to the full album of this passage
. Hover the mouse over the photo
there to find a panel that allows more detail up to full camera
resolution. (SmugMug is really cool if you like your photo's and want to get them organized!)