I would say to take a look at how people teach *you* that is effective....then pass it on. It didn't sound as if people higher than you tell *you* how to block or dodge, and they don't tell you what they are going to throw. It just happens.
IMHO, this is the best way to learn, when doing free sparring. You can do "three step" sparring, where you are like six feet away from your partner, and you are throwing one move at a time, in the air, while they are blocking your moves in the air. This will train them how to block what moves. However, I am a strong advocate that what actually works in free sparring is to spar at just above the level of the lower belt you are sparring. Give them something to rise up to, not something they can handle easily. Let them figure out what is going on. Don't pummel them mercilessly (I don't hear you saying you do), but challenge them.
Before I start sparring someone lower than me, and usually after, I will have a quick discussion with them, pointing out that where they get hit most often is where the holes in their defense is. Then, they get to figure things out. If they want pointers from what *I've* seen when sparring them, I'm happy to share. However, they have to want them.......if they are not interested, then they will learn the hard way...
Again--*challenge* people, don't figure it out for them. You can stop (briefly) in the middle of sparring them to point something out, but I wouldn't do it for the majority of the moves. One I use is to tell lower belts when best to come in on my--I tell them things that I have noticed I tend to do (I am working on fixing them!!!), so they can start to see patterns and exploit them.
Ah, well.....my opinion. As with all things, your mileage may vary.
Peace--