One other item on the "nay" side--if you're at timberline or above where campfires are not allowed or there are campfire bans because of the fire danger (every summer in the northwest), you're going to have to carry more fuel to cook those fish, which will add to your pack weight. (That assumes that otherwise you only boil water to rehydrate dried food--if you're a gourmet camp cook, it won't make any difference.)

There's also the issue of needing either a fry Since my protein source would otherwise be dehydrated, any food weight I save will be more than offset by the tackle, the frying pan and extra fuel. In other words, I'll be doing this for fun, not to save any pack weight!