Bad sign if nobody can comprehend one's code?

If a coder writes code that nobody other than he can understand, and code reviews always end with the reviewer scratching his head or holding their head in their hands, is this a clear sign that the coder is simply not cut-out for professional programming? Would this be enough to warrant a career change? How important is comprehensible code in this industry?

Consider these C examples, compare:

if (b)
  return 42;
else
  return 7;

versus:

return (b * 42) | (~(b - 1) * 7);

Is there ever an excuse to employ the latter example? if so, when and why?