Monero Mining

I wonder if you could chain multiple xmrig proxies to a single xmrig proxy.

My scenerio for this would be if i ran a computer support business and the contract was that each client would dedicate idle cpu time to mine. So say each client had 20 machines, those machines would mine to an xmrig proxy which would be set to mine to a proxy that i have easy access to. That way instead of 200 computers (10 clients with 20 machines) all hitting a single proxy the main proxy would only have 10 connections to it. That would make switching pools easier too since only a single proxy would need to be changed instead of visiting 10 different sites to change each one.