"But these are just the rocks in the river that the currents and eddies swirl around, they're the visible aspects of sentiment and changes that run deep and are

"But these are just the rocks in the river that the currents and eddies swirl around, they're the visible aspects of sentiment and changes that run deep and are invisible unless you're in the trenches and paying close attention." You can really turn a phrase. (This is a complement.)