I buffed my Strength to be my highest attribute and learned an instance of Blocky Script technique where up to now I have been learning Angular Script technique (with Perception as my highest). Valmo suggests that you might only learn the techniques in fights where you don't use a script technique.
I used the Angular Script technique to get the Angular Script effect. Then on the next round I used Blocky Script technique and the Blocky Script effect replaced the Angular effect. Nothing notable that I noticed post-fight. So there's no obvious advantage to chaining two of them together.
EDIT: Also nothing for chaining them together in the same pass.
EDIT AGAIN: Oh, yeah, so far nothing that I've noticed from using the techniques with the odd sketchbook equipped.