Diesel engines have the greatest torque and thus pulling "power" at the the low end or the beginning of the curve, that is when they start, there are persons that are aware of any change in the operation of a vehicle and there are others that will not sense anything out of the ordinary, it is an individual's natural ability to sense or recognize the situation or be completely oblivious of any thing at fault.
It is very easy for a human to forget of miss a step or action, specially when there are other thoughts or are pressed for time or just simply distracted.
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