Pinging anything DID help me while playing Counter-Strike back in the days (2001-2002), had a crappy ISP then (10 Mbit split between 40-60 others).
Of course you won't take my word for it and i got no proof..

There may be other ways to lower your 'ms' in WoW like this TcpAckFrequency/TCPNoDelay registry 'hack'.
Works for me anyway.. playing with less then 100 ms, my friend next door with the same ISP and all got around 250-300 ms.. same as i did before.