[catacon]

I do a fair amount of automotive racing and this is often an issue in those events as well. Many people want fancy/stylish/funny/whatever numbers and class letters on their cars so they can be unique. Unfortunately, when a car is flying by at 100+ MPH, those shiny yellow numbers are real hard to read on a white car... So many groups have gotten very strict over the years about what number styles and color combinations are acceptable.

While our robots aren't going 100 MPH, there is still a lot of commotion on the field and those fancy-pants numbers can be difficult to spot. And what one person (an inspector) may think is easily visible, a ref or other volunteer may find unreadable. Standardized black letters on a white background are without a doubt very readable and save inspectors from having to make a judgement call about readability. Save the creativity for team logos, shirts, driver stations, and other parts of the robot.