GMAT Sentence Correction (SC) | Re: The westinghouse air brake, first demonstrated successfully in 1868, h

Hi Mike,
Thanks a lot for the entire content. It was very helping and insightful.

I would also like to know your opinion on cases which are recommended not preferable on GMAT. Cases like below:

Usage of 'being'
Usage of'[PREPOSITION]+[NOUN]+[VERBing] '
Usage of 'Past perfect' when sequence is clear - our case

All these cases among similar others are not outright wrong but less likely to be correct. They may fit well given other choices are not better. I want to know how should I approach such choices? Should