1.0.1 Bonus damage from weapon not applied always

My favorite anti-worm staff. Noticed that sometimes the damage scored to worms is normal. Happenned fairly often. My observation so far indicates that it’s a problem of projectiles. Area attacks always did 3x damage, projectiles (shard and splash definitely) not. (but the splash from Ice Splash did, when the projectile itself didn’t). Ice ball never failed.

Also I noticed Ice shard projectile sometimes change orientation by 90 degrees, flying sideways.

What is your opinion about weapon damage? What is the best weapon that has a great damage?