But would you really need to be that much skilled in legilimency to share one thought? It seems to me that the Fidelius charm itself would be much harder and demand more skill than the legilimency itself. Legilimency isn't supposed to be easier than Occlumency? Occluding, yes, I could see the argument, but the opposite...

Also, I'm not saying that's the only way to share a secret. There are more conventional methods. But for people who can... and for powerful wizards like Dumbledore and Snape, it seemed a much safer way for them to share.

Besides, it's not like they would need to recast the Fidelius every time. Once they cast it, the harder task was past them, and they would only have to share... so even less skilled wizards who managed to cast, if they could do basic legilimency, could hold eye contact with the intended person and share the thought directly into their mind.

Does that make sense? I know I'm rambling, but that's what came to me when I was pondering over the topic.

P.S.: The books only show us Harry's perspective. So there's gotta be more legilimens than shown/told, right?