Question

colloquialisms and slang are important in when greek meets greek because?

Answer 1

Just a minute.

Answer 2

ok you might want to try this site:
http://www.dailykos.com/story/2011/03/20/958188/-The-Mad-Logophile-Olde-Slang#
It may help if it doesn't you could try asking @beccaboo333

Answer 3

I think it is to help understand the characters better or to understand the plot better.