For my application I have found it is more complex about provisioned vs consumed capacity. I get throttling all the time when consumed capacity is a third of provisioned capacity.
You also need to care about how DDB does its underlying partitioning. It would be nice to turn the knobs and be able to trust you will get X reads/sec and Y writes/sec, but that is only true per node! Unfortunately, DDB gives you zero information about how many nodes your DDB table is running on! (Yes you can guess pretty well if you keep track of your usage rate and do some math).
So when provisioning, you need to be aware that if you have 100 provisioned read ops, but you have data on 5 nodes, you really only have 20 reads/sec if one key gets hot.
I agree it's pretty easy operationally, but you can get burned if you don't know how it works under the hood.
