I would suggest the 35lpi or coarser- especially on dark garments. Remember, screen printing has horrible dot gain, and printing a reversed out image(shirt showing through), such as the one in the article, always tends to close in. Plus, often times the print shop has to create a CHOKED base. For instance: What if they wanted to print this in bright green?
I like the 22.5 angle (prolly defaults to 23) on ALL films ALL the time. That seems to minimize moire.