Trying to sweep the leg with an arm is just a bad idea in general. The two big reasons I can think of are:
1) Puts your head low - easy to get hit with their leg, shield, weapon, etc
2) Makes them fall in an uncontrolled manner - can break their arm if they put it behind them to brace their fall
The best bet would be to swing for their leg to try and gimp them. Wrap their shield wide and try to get enough force from your wrist to get the connecting shot to have enough force to count.
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Going from Angmarth's post -
Yes, we do bash and grapple a LOT around here. Personally I love bashing, even though I'm only 6' 160. With enough practice you learn how to take the hits and shift the advantage away from the person bashing you.
The one thing I want to expand on with teaching is falling safely.
~?~
On second thought, I'll go start a thread in general so everyone can read it.
Thread here
Uruk-Hai Serpent Breed and proud
Victory though intensity, tactics and glorious death!
Daemarth: <On the topic of some people just can't get along> it's like sticking me and Kegg in a room... and I keep punching him in the f'n face, and someone looking into the room just keeps telling him that he just needs to get along with me...