Recently, a few whole-program static slicers for the C programming language have been developed, permitting a variety of hypotheses about time--precision tradeoffs in program analysis for software engineering to be tested. This paper reports an initial investigation into these claims through GrammaTech's CodeSurfer and UCSD's Sprite research prototype, which represent two very different approaches in the program analysis tool design space. First, it was found that algorithmic superiority tended to provide large improvements in relative precision in select cases. Second, a number of non-algorithmic design choices had a substantial and sometimes unintuitive influence on slice results. Third, considerable expertise and time was required to d...