It happens. Civil servants, foreign governments, interest groups discreetly talk to opposition parties in advance of an election where a change of power is expected. Also, the British Government secretly talked to the IRA for years while they were “at war” with us. That’s how we got where we are today in NI. Who knows. Perhaps the DPP/government and KMT have more sense than we’d credited them with and the KMT are secretly representing the government.
Talking to your enemies without preconditions is good. It doesn’t mean you have to make unacceptable concessions. It just means you’re talking.
The problem is the KMT acting as if they have the God given right to represent Taiwan and really ought to be the Government if it weren’t for some messy thing called electoral politics/circumstances, and the BBC representing it as such.
It’s like Al Gore acting as if he were President of the US and going round making “treaties” rather than just being a lobbyist.