GmatLa有考友是这样理解的:
同位语也是修饰语,在修饰被同位的词语或句子,A的主干是:Warren was near the center, from 1765 to 1789;E的主干是:Warren was near the center, from 1765 to 1789, and this vantage point made her a good historian. 可见后半部分其实是重要的内容,应该作为独立句与主句平行,而不是作为主句的修饰部分。
同位语与状语相比时,通常同位语更有利于表意;但这里同位语与独立句比较时,却是独立句能更好地表意。