# Block Diagram Reduction: Is it necessary to do it stepwise?

Just a short question: Is there any usefulness in doing block diagram reduction piecewise?

The reason I am asking is that I find it much (!) easier to just find the final $\frac{output}{input}$ transfer function using mathematics (the brute force method), but my professor does it stepwise.

If I am to do it stepwise, I still feel like I have to do it mathematically, rendering the stepwise reduction pretty useless as far as I can tell.

I realize this seems like a banal question, but I cannot find anything answering this question is my controls book.

• Why don't you ask your professor why they do it the way they do instead of asking us to speculate on your professor's motives? – DLS3141 Sep 14 '15 at 19:27
• Because I did not want to wait until Friday. I was just curious and hoped for an answer before then :) – Akitirija Sep 14 '15 at 19:52

When you are solving a problem in the real world, there are 2 main important requirements