Because I prefer processing audio information, I have a tendency to assume that others also prefer to talk about ideas instead of reading about them first and then discussing them later. But, since many people are more comfortable digesting information on their own before offering suggestions, this can get me into trouble.
It's important to acknowledge that everyone is wired differently. When working to get buy in for an idea, it's worth asking how people feel they do their best work. Since the goal is gather meaningful feedback and to give people a chance to voice their concerns, try to avoid making people question whether they could've expressed themselves better if their opinions had been solicited differently. To do this, err on the side of sharing materials ahead of time, so people have time to prepare if they want to.