No thats not what cloud technology does....

imagine you have 4 horses connected to a carriage (which has 4 wheels). Is one horse each pulling 1 wheel? or are all 4 horses pulling a quarter of the load?

If you have a cloud of 20 servers, with a processing power of lets say 20 billion processes (or whatever measurement you want to use), those 20 billion processes would be used to run all 395 TW worlds... if one server goes down, then all 395 worlds would be running on 19 billion... it wouldnt affect just one world, infact there should be no effect at all, as there should always be spare capacity within the network (unless suddenly all the world comes onto the same daylight hours?) - so no one should notice anything going wrong.
Servers can be added and removed from the cloud with little or no impact on the end user