Oh I have plenty of that too. But it's usually the case that saying _anything_ reasonable is enough of a foot in the door to a wider conversation. And it's a lot like creativity, or math, or music... the more you do it, the better you get at it.

It's like when you learn a new language, one of the first things you learn is how to say "I don't speak X well, please slow down" in that language. Same with debate: learn how to say "I'm trying to better understand" to prime the other person for a conversation. Sometimes they'll start talking for you–that's even a common negotiation tactic, to let the other person talk to basically give you a few points to think about questioning/rebutting, or look for contradictions.