Re: You are NOT "FISHING"
Okay, if he thinks he's "engaged in fishing" under the Colregs, then he's required to show the proper lights or day shapes (two cones with pointy ends meeting, Rule 26). So that day fishing boat? No cones, no right-of-way. And virtually no one without a deep-water license shows, or knows about, day shapes so the sailboat will almost always win (at least legally) over the fishing boat that's not "engaged in fishing" but thinks he is.
And yeah, there's no "we're racing" provision in the regs either. It's a courtesy thing but not required. So be courteous.