My main argument is these numbers mean absolutely nothing. I imagine fewer Washington & Lee alumni keep in contact with their school than William & Mary based on Geography. Washington & Lee is located in Lexington, VA a town of 6,000 people in the middle of Virginia not near anything. Graduates likely leave the geographic area and do not keep their school updated.
William & Mary is also located in a small town of only 15,000, but it is near the Hamptons and more employment opportunities making it more likely that alumni keep in contact with the school. Here is a link to google maps showing where the two schools are located. https://maps.google.com/maps?client=firefox-a&q=williamsburg+va&ie=UTF-8&hq=&hnear=0x89b0890a4495aa1b:0xc14b30175e160eaa,Williamsburg,+VA&gl=us&ei=1TqJUuHpHsSfiAKv8ID4Aw&sqi=2&ved=0CN4BELYD
With that said the numbers mean very little in my opinion and as I displayed above you can manipulate them to say whatever you want. However, even if the numbers are 100% accurate there are more than 50 unemployed William & Mary Grads and well over 50 Washington & Lee Grads that are employed and it really shows it is up to the individual more than the school.
Maybe William & Mary does give you slight edge over Washington & Lee and I would imagine that would be due to location more than anything else, but even assuming these numbers are accurate you are not guaranteed to succeed from William & Mary nor are you guaranteed to fail from Washington & Lee.
Bottom line is there are graduates from every ABA school in America that are employed and doing well for themselves conversely there are graduates from every ABA school who have been unable to pass the bar or find employment.
Whether you succeed in the legal profession has far more to do with the individual than the name of their school at least in my anonymous internet poster opinion.