I have one little patch of grass that's thick as carpet and I'm wondering if the extremely heavy application of soil conditioner/kelp help is behind it. the whole yard is treated the same, organic with 2oz/1K of conditioner prior to rain but this one patch gets whatever is left over in the bottle, probably 8oz/1k and since applying the grass has gotten thicker and thicker. I'm wondering if I couldn't apply conditioner to the whole yard this heavy to get the same result but since it's 20K I'm afraid of the cost without proof.

It does seem to help considerably with thickness, yes, although I'd caution against wide overapplication. It could have negative consequences.

under normal application rates how long does it take to increase thickness assuming you're following a liberal organic plan?

That depends, really. A soil that lacks a resource like P or K may never thicken to your satisfaction. Very dense soils will be slow, sandier ones much faster. I'd say that you should see a change in the first year, absolutely, and I'm being pretty conservative with that number.

Combining it with heavy organics definitely accelerates the process and keeps the soil open, so that helps as well.