“Yeah, I could do” means they won’t, and it’s known as positive blocking.
Whether they mean to or not, the person saying “could do” has no intention of doing the thing. They either don’t want to offend you, or they don’t realise they’ll never get round to it.
You know what happens when someone suggests something you really like the sound of. Your ears prick up, you lean in, you want to know specifics. You’re pulling up maps and your calendar and figuring out when you can do it. You make it happen.
People who know you and know what you want are far more likely to be on point with their recommendations.
If someone’s saying “could do” in response to your suggestions, it’s probably time to ask more questions. Find out what they’re into and find out what they’re trying to achieve. Listen carefully and filter your response for relevance.
If you find yourself saying, “could do” in response to other people, work out why. Is it because they have barrelled in with unprompted advice? Is it because they have suggested something that really isn’t up your street, or is it you that doesn’t realise you’re positively blocking?
Our actions reveal our true values but our language holds clues.