suspicious FVH init code in DefaultSolrHighlighter even when FVH should not be used

Rich Hume reported gettting errors from FastVectorHighlighter, evidently while using the the surround query parser, even though he was not trying to "useFastVectorHighlighter"

my naive reading of the code leads me to believe that DefaultSolrHighlighter is incorrectly attempting to initialize a FVH instance even when it shouldn't be – which appears to cause failures in cases where the query in use is not something that can be handled by the FVH.

Not sure how to reproduce at the moment – but the code smells fishy.