I really enjoyed this golf - there are so many unique approaches one could take. Here's one at 78: 
sub is_fibo {
  push@_,length$&while$_[0]=~/^|(.)\1*/g;{@_>3?pop==$_[-1]+$_[-2]?redo
+:0:pop==1}
}

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   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

In reply to Re: (Golf) Fibonacci Strings by MeowChow
in thread (Golf) Fibonacci Strings by danger

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