I've ridden down MLK a number of times heading south and have never had a problem keeping up with traffic, due to the downhill.
Where there are two lanes the traffic lights are timed slower, traffic isn't moving that fast. Where there are four lanes cars can easily get around you even if you are going slower.
Frankly its less hectic than williams / vancouver. Just stay in the middle of your lane and signal what you are going to do.