Ye Xiwen very clearly knew that there was a huge disparity between a sage tool and Great Sage tool. Therefore, he had tried many methods to make the Heavenly Source Mirror break through... He wanted this top sage tool to become a Great Sage tool. After all, he would have a big hidden strength once he had a Great Sage tool in his hands.
Great Sage experts that used sage tools could be found everywhere. The Lord of the 'Dominating Heaven Dojo' was an example of this... He was indeed a Great Sage expert. However, it was clear that he was only a mediocre one. Therefore, he used merely a top sage tool... He didn't have a Great Sage tool.
It didn't matter whether a person wanted to fight against a Great Sage expert or escape from the hands of one... It would become very easy if that person possessed a Great Sage tool.