Ron wasn't keen on telling the DA anything - if the Order was liable to jump in too eagerly, Ginny and hers were bound to be no better. Like Hermione said, it had to be a secret. Still ...
"We should let them know something's going on," he said. "Just so they know to be careful. But if they know too much, they are going to try to help. You know that." Not that it wouldn't be nice to have a little help, especially from the inside; but getting them caught up in it probably wasn't worth it. He doubted the DA would be lacking for opportunities to stick their necks out, anyway, even if all of this went according to plan. Which it never seemed to.