The idea here is that you use parallelism to implement operations like caching which can decrease the number of serial steps required for a thought, so that more of them can occur one after another. In the simplest case, if you were already using a serial processor to emulate parallel computers, adding parallel power increases serial depth because you need no longer burn serialism to emulate parallelism.
Oh, so diverting serial processing cycles to get serial depth instead of getting half the depth over two independent tasks. I thought the sentence was saying something else entirely: that a better algorithm does the same thing except with higher serial depth over fewer processes.
The idea here is that you use parallelism to implement operations like caching which can decrease the number of serial steps required for a thought, so that more of them can occur one after another. In the simplest case, if you were already using a serial processor to emulate parallel computers, adding parallel power increases serial depth because you need no longer burn serialism to emulate parallelism.
Oh, so diverting serial processing cycles to get serial depth instead of getting half the depth over two independent tasks. I thought the sentence was saying something else entirely: that a better algorithm does the same thing except with higher serial depth over fewer processes.