Dialect?

One of my MCs is an African American professional who suffers anxiety attacks brought on by the stress of his career. The roots of his emotional problems are explored, and in a nutshell, those roots are in his childhood on the mean streets of Philadelphia. He resisted the call of the street and was a good student and good citizen--but that meant to the gang-bangers, etc., he was an Oreo.

The plot calls for him to return to inner-city North Philly and interact with his bad-boy younger brother.

Here's the situation I'm in: I've pitched this to about ten agents, and got the standard (in some cases, instant) rejections. But two agents were kind enough to offer a brief critique. BOTH wrote that the MS may contain racial stereotypes.

I've read several novels that feature characters from parts of the country known for distinct dialects/accents (the inner city, the deep South, New England), and most characters speak as though they are Midwestern college students: ("JaMarcus and I were only planning to rob him. That's when the shooting began.")

When I read that, I want to scream, "aw come on!" People from said regions of the USA almost certainly don't talk like that.

One published writer on another forum pointed out that the rule is to use standard, readily-understood English, and let the reader add the dialect in his/her mind.

What do you think?

Without knowing specifically what the agents were getting at, I'd say you don't want your characters sounding like educated middle-class if they're not, but you shouldn't get too detailed in the dialect, either, because you don't want your readers to stumble over the dialogue or get offended. I'd take a middle-of-the-road approach. 

Not this:

"Me an' JaMarcus was just gonna rob 'im an' den dey start shootin'"

But this:

"Me and JaMarcus were just gonna rob him and then they started shooting."

A reader can fill in his or her own version of the dialect with just a gentle nudge.

That's the opinion of a newbie, anyway, but I hope it helps some.

Some dialect can be highly useful in producing good dialogue.  Many good writers do use dialect. 

But there are two rules that nearly every good writer applies.  1. KNOW how real people who use this dialect speak.  2. Use it sparingly.  Like cayenne pepper, a little bit goes a long way.  A touch seasons, too much simply burns.