Hello.
Recently it has come to my attention that any and all attack speed boosting buffs in the game do not affect automatic weapons. This includes perks like Fast Shot, Ain't Like That Now, Slayer, and Melee Hacker, but also includes Rushing Water. While on the surface it seems this would cause Blood-Nap to be an absolutely godlike weapon, I believe there is a max attacks per second in the game. I recorded myself with all the bonuses I just listed, spamming attack with Chance's Knife (tied for fastest non-automatic weapon in the game with all perks), and I could only get 4 attacks per second, give or take. This is contrary to what I calculated of course: The GECK lists 4.1538 attacks per second with this weapon, and that x1.1x1.2x1.2x1.3x1.5 would net over 9 attacks per second. I don't think it's just due to the limits of my clicking speed, although there's no way my fingers can click 9+ times per second.
I believe I did manage to click over 4 times per second though. So that's weird. So I wonder: Did Obsidian know that the weapon is already basically at max attack speed?
All of these things have a large impact on which weapons have the highest DPS in a given scenario.
EDIT:
With a simple mod that increases the buff of Ain't Like That Now from x1.2 attack speed to x5 attack speed, I think I have shown that attacks per second can't go any higher than 4 attacks per second on Chance's Knife. With Medicine Stick it looks like it's stuck at 3 times per second, same with Old Glory.