It is quite funny, really. I have found my self questioning my own grammatical knowledge, which albeit is not that great. But still... I keep getting hit for 'passive sentences'.
.... and fragments.
I don't suppose, though, that it would matter what engine you used, there will never be any accurate way one can measure inflection in sentences; that quality that makes the sentence make perfect sense, at the expense of throwing a few rules to the wind.
Sorry about the thread... just me getting philosophical in my old age.... :-;