See rule 3.4 B
The 36.7 is a weight sensative boat. Class crew weight is 1,550 lbs. If there wasn't a significant advantage to heavier sailors, then they wouldn't have that rule. Stack 9 people on the rail with one driver (10 total) and it's a huge difference. That's 1500 lbs of righting moment. And that's why you see people hiking when racing. It makes a big difference.
Theonecalledtom, it's really hard to tell if you're going sideways b/c there is nothing to reference the boat against. The waves are fluid, your wake, etc. But judging by heel angle, it doesn't look like you would be going sideways. The 36.7 (like most boats) really suck when you put the rail in the water. Flat is fast.