I am sure that worked for you and I do not want to undermine the importance of simplicity. However my question was drawn from my previous experience where it was one hell of a task to keep the spam bots out.
Therefore, just to offer a counterpoint, I would like to register my experience here. A random name surely did not do the trick for us. Simple tricks like creating a random hidden field would be broken by spambots in less than 48 hours. It took a great deal of expensive WAFs like Barracuda and a lot of Lua scripting combined with cookie analysis (and overall request header analysis) to detect spambots with only a 90%-95% accuracy and keep them out.
Therefore, just to offer a counterpoint, I would like to register my experience here. A random name surely did not do the trick for us. Simple tricks like creating a random hidden field would be broken by spambots in less than 48 hours. It took a great deal of expensive WAFs like Barracuda and a lot of Lua scripting combined with cookie analysis (and overall request header analysis) to detect spambots with only a 90%-95% accuracy and keep them out.