Subject-verb agreement question: represent or represents?

Neste texto:

"This however is still largely dependent upon the number and optimal spacing of gear ratios for each unit, and whether or not the elimination of spooldown/accelerator lift off represent a significant enough gain to counter the slightly higher power consumption of the automatic transmission itself."

penso que o autor cometeu um erro de concordância verbal. Ele pretendeu "represents", mas, ao invés disso, escreveu "represent". Did I hit the nail on the head on this one? No? Please tell me why not.