Feng Fei-fei and Teresa Teng as cross-strait ambassadors

In the wake of Feng Fei-fei’s death, much emphasis has been placed on similarities with Teresa Teng, not least because both pioneered Taiwanese popular culture on the mainland. It’s my impression that Teresa Teng was somewhat more efficient in this respect, perhaps because of her impeccable KMT/military background. Was Feng indeed playing second fiddle on the mainland? If so, how to explain this?