But I would in theory defend the use of comma splices so long as the writer knows how to use them to achieve specific stylistic effects, or if they are part of a deliberate style. For example, I'm thinking of stories where the narrative prose is strongly connected to the point-of-view character's thought process, at which point comma splices may be used to indicate the disjointed or madcap nature of run-on thoughts or panic. They have a potential place in dialogue as well, because people don't always speak with exact grammar and typically, at least in my experience, don't speak with semi-colons.
Even if justifiably employed, however, their use should be sparing, and from your description it sounds as though it was in this case anything but. The semi-colon is a noble creature; it should at every rhythmically suitable opportunity be slid through the guts of a sentence, the cold blade of grammar.
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