Wouter,
you are constantly comparing the Inter 17's on the NL with your selves.
I have to take exception to this now:
However I have seen many times that teh I-17's got nailed to the wall by other boats. Overhere in the Netherlands the Inter-17's are racing in the slow boat fleets because of the slow rating of these boats, that is when the 17's are flying a spinnaker while the other boats aren't ! A few times I saw the lead Prindle 16 (an old and medium speed design if there is one) riding the lead I-17's tail. I have a really hard time believe both these specs and the performance promise that comes from it. But make up your own mind; this is the info I have.
The reason is that they are not good sailors.
How do I know ?
I've a good mate who was over at Texel a few years ago (2 or 3).
He started well and was hit by a Tornado and had to land his boat and make repairs to one rudder.
He then went back out from the beach and re-joined.
He then passed all of the NL Inter 17's that were sailing. Now they did not have Kites. OK so you would expect him to pass them sailing single handed - they were sailing 2 up without kites and it was blowing about F5. Why, the boat can take it - I've sailed mine 30 kts with the kite up and was loving it.
When he was back in he happened to spot them landing and asked whem whay they were asiling 2 up, answer - too windy for sailing single handed. Do you have Kites he asked. Oh, yes. Much, much too windy for them !!!!
Please compare like with like.
I can lap (in a 3 lap race) one of the guys who is learning to sail his Shadow (Same SCHRS as the Inter 17) at my club. Does that make the Shadow a bad/slow boat. No.
BTW I would be expecting to LAP a P16's on most multi-lap W/L races.
If the Handicaps are similar and the boats are not performing the same, one of 2 things is wrong
1, The cacluation/measurement system is wrong
2, The sailors are not of the same skill.
