I use back post single crochet in three different ways in my linen stitch-based patterns, simply replacing the sc in linen stitch with back post single crochet.
1. As a textured divider
In the Maraska sweater it visually separates the lace and solid stitch patterns and adds some stability. It prevents the lace pattern from stretching at the points with large chain spaces.
2. For colorwork
When worked in a different color, it creates mesmerizing dashed lines. I love them so much! I used BPsc for colorwork in the Smoothie shawl, Vibe shawl, Kraynebo sweater, and the recently released Linen Flowers. 
Mixing the linen stitch with the back post single crochet rows helps blend the colors. If you ever plan to make a temperature project (or any other project that involves mixing lots of different colors), keep this idea in mind!
It also works beautifully with variegated yarn, this is my go-to solution for mixing complex colorways. It always works!
Both colorways of Malabrigo Rios (Whales Road and Marte) used in the Kraynebo sweater are multicolor shades, and just look what a lovely effect this technique creates!3. As an edging
It makes a perfect edging for linen stitch-based patterns: it firms up an edge, can be worked tighter to reduce the circumference (for cuffs and hems), or relaxed (for shawl edges). I use it often for pieces that don't need anything bold or eye-catching but would look unfinished without some kind of edging.
It's the same dashed-line texture, just worked in the same color to create a thicker, firmer edge.
And in the Linen Flowers, it is used for colorwork, additional texture, and edging, all at once! ◍•ᴗ•◍
For the edging, I worked two rows of BPsc. A single row would look like a continuation of the stitch pattern. Working it twice created a thicker, heavier edge for better drape and that little finishing touch. ◍•ᴗ•◍
Other Linen Flowers reels on Instagram:
Joining both shawls into a wrap
Linen Flowers colorwork (close-up)
Green and white colorwork
How to: Linen Flowers colorwork (stitchwork)
How to: Switching colors in linen st based patterns
