No non at all. That's why I lock the knot I place to stop it opening and closing during the fight. If your still worried just add some silicon tubing so it forms a kicker.
12lb mono hook link is my fall back rig. Fished straight though with double bottom baits. Just whip back up the knotless knot a couple of times to lock it in place.
hiya lads what knot do you use to connect flourocarbon to mono?
The flouro im going to use is 20lb to a 12lb mainline. Would the back to back grinner be ok?