I had originally planned and tried in vain to get the Hazel bundle to work in both a stretch twill and a Ponte knit, but the variations in stretch percentages were just too great if I wanted to maintain a quality pattern. I like patterns with a lot of options, so I've spent the last few months working it out.
Plackets, welts, double welts, single welts, and facings all basically work on the same premise. They're a bit scary at first and often pattern markings do not help with the anxiety. Pattern markings often make it look like you're doing some blind sewing on markings you then cover, hope you hit them, then cut a hole in your good fabric...riiiight.