[NTG-context] Section format using /def

I, apparently, do not understand the syntax and/or uses of /def. I am trying to make section heads appear in all caps and underlined. I originally tried to just use \setuphead, but found that I using the "textcommand" option I could only either capitalize or underline and not both. I then figured that using a macro was my next best option. Below is what I tried and it does not work. Can someone tell me what I am doing wrong? \def\mysectionhead{\WORD\underbar} \setuphead[section] [number=no, textcommand=\mysectionhead, style={\tfa\bf}] Thanks, Mike