I’m always troubled when people use the “More – than you’ll ever know” speech idiom.

For example: Your help with my child’s tutoring helped our family in more ways than you’ll ever know.

At the very least, it’s faint praise.

I mean, do we ever know all the ways our actions help someone, or are appreciated by someone, or encourage someone? Your statement implies that normally the helper is supernaturally omniscient about the results of their actions, but this one special time, due to the magnitude of their benevolence, they lost that super-power.

No. I say that it would be true to comment thusly: Thanks for passing the salt. You increased my dietary joy in more ways than you’ll ever know.

I recommend that you start doing this.