On the wiki, it states: "Attack speed increase value for swords has a hard cap, which mostly affects the cutter/spur line."
Presumably, that cap, at least for cutter/spur, is limited at less than six "points", otherwise it wouldn't warrant a specific mention. Has anybody determined what that cap is?
I've got a Dread Venom Striker with a medium bonus (+2). There's a noticeable difference when I use a Swiftstrike Buckler (+3, total +5). So if there is a cap it's somewhere between +3 and +5. I'll probably cave and finish my Vog set sometime in the next week as I am getting burned out trying to craft UVs so I'll let you know what I can observe then if someone doesn't beat me to it.
Of note, on the Speed bar meter it only takes a medium UV to hit 10 bars. Not sure if that's worth anything.