I don't know if anyone else does this, but I found a nice technique that helps me in battle.
Use the girders to trap in other works when they are in corners or holes.
Stalls them off.g

Lol, I should try that! The funny thing would be that if they can't use the blow torch they'll have to blast themselves out and get hurt!

loooool that shall be a trick?? a tip, if you only have the explosive wepons then take the cluster. put it in a corner and even if youre near at it, you wont get a damage and if its extremely few.

im writing about the ds version, but i think its not much different from the psp version

This is one of the main uses of the girder, it's nothing really new...
People were doing this back in the days of the first Worms game on Amiga and DOS platforms.

I hate it when someone does this! its rude and not being fair! I dont do it! Trapping someone with a boomerang is acceptable, It takes skills to do that!

how can you trap someone with the bumerang o_O ???

\( o")_ - - - - - -<\("o )/ You make sure the boomerang mouth sticks to the ground and a wall with the worm stuck in between.

sweet boomerang moves. I like to use it as a step sometimes if I don't have rope or jetpack etc.