couldn’t we increase the performance of hard disk drives by adding more read/write arms?

Question

instead of waiting for a full revolution for the data to come back around, multiple arms can get to data much more quickly. Also, more arms means more read/write speed..

..right?

In: 4

Answer 1

You can accomplish basically the same thing with multiple drives that have the same data, which is cheaper and easier to implement. Aka, RAID0.