There are two different kinds of chow fun:
1) dry - b/c there is no sauce and the noodles are brown from the sauce, stir fried with bean sprouts and beef
2) the noodles are still white in color b/c the noodles come in a gravy sauce, stir fried with chinese broccoli and beef.
You and I both prefer 1. It sounds like you must have had 2 on your most recent visit. Be sure to specify when you order. Most restaurants will make it both ways.
Often times, I have noticed that the noodles prepared dry are shorter, more delicate and separated, while in the other preparation, the noodles are often left longer and sometimes stick together from when they were sliced. I'm probably not making much sense right now, but if you eat chow fun often enough you will probably have similar observations.