You're making it sound like a simple parameter optimization issue, but it's hard to imagine a mutation that breaks out of the "fall forward as far as possible"

You're making it sound like a simple parameter optimization issue, but it's hard to imagine a mutation that breaks out of the "fall forward as far as possible" paradigm without discarding the parent phenotype entirely, which would defeat the purpose of using an evolutionary algorithm in the first place. Anyway, the point was that a complex optimization problem resulted in an unexpected "suicidal" phenotype, i.e. falling over instead of walking.