Perhaps there is a place for a simpler alternative. My comment was pretty tangential to this discussion about the merits of SPI vs USB vs whatever. My point is that I believe some benefit can be had by software developers in understanding how components can be integrated together using a primitive as simple minded as SPI. I used the qualification "some" again, as well. I don't offer any revolutionary insights, but if you survey how SPI is used in practice, you'll learn some things of value, even if you never use SPI yourself.