Maybe you already double-strand your crochet with pleasure. This topic first occurred to me last week when LeeAnn said, "I've always been a little ambivalent about patterns that call for double-stranding the yarn and wondered what the reasons would be for doing that."

I thought I felt the same as LeeAnn about it. After all, sometimes yarns tangle when I've crocheted them together. If one ball is wound looser, its strand will loop around the other strand I'm crocheting with, and this could make my stitches unevenly lumpy. 

Over the years I'd come to think of double-stranding as fun for mainly knitters. I'd noticed that yarn companies offering "carry along" yarns or threads almost always show them knitted. I might crochet two strands of something together out of necessity, but not for fun, like knitters seem to. Or...would I?

Turns out I've gradually changed about double stranding. LeeAnn made me realize I've been doing it a lot and liking it. In fact, I have too many examples to show here.

Special Stitch Effects

The most fun of all has been seeing the ways star stitches and love knots change when I double up the yarn. Four years ago, when I designed the Lovepod Boa (see image, above left), I just assumed it was a nice feature of that particular design and yarn choice.

More yarn strands make star stitches starrier. Extra yarn overs do too, but with extra work. By yarn overs I mean that while making a star stitch, one can yarn over before pulling each loop of it, and this adds strands to the star. I find double stranding to be simpler and faster than this. Who would have thought?

Creative Excitement!

No, wait. The most fun of all has been doubling color and texture options! The Electra Wrap opened my eyes to that (see top right corner). Crocheting a strand of lace mohair with a strand of a fancy slippery sequined thread makes each yarn easier than if crocheted alone. Using love knots makes it exciting, beautiful and fast!

Thanks to Electra, I noticed that crocheting one strand of fine mohair yarn held together with a different yarn changes that yarn. The mohair often seems to melt into the other yarn while adding a hazy tint of color, like painting with watercolors. So I tried pairing a pale gold mohair yarn with a dark gold cotton and rayon yarn in my stash. 
The combination fixed so many problems I had with that dark gold yarn. It feels very luxurious, and it's now a much nicer, buttery color for me.

Some yarns seem designed to give the same effect as double stranding. That's when I selected Kollage Delightful for a Lovepod Boa swatch. I also think of Artyarns Cashmere 5, Trendsetter Dune, and Fiesta Yarns La Boheme (pictured below).

Double stranding can add special design options, too. For the Sterling Bag I used one strand for the main bag part, then doubled up the yarn to give more dramatic impact to its decorative overskirt.

Common Practical Uses for Double Stranding

"Fix" a self-striping yarn. Sekku Coasters is a memorable example. The yarn was trouble and made me cranky: it's lace weight, sticks to itself, and the garish colors changed abruptly. Just crocheting with both ends of the same ball held together fixed everything, including my sunny disposition! 

Include beads with holes that are way too small for the yarn. The Aquamarine Poem-Lariat, for example (blogged here.) This is also how I got the pearls into the Bronwen Capelet.

Change the thickness of the yarn. To use a thin yarn for a pattern that calls for a thicker yarn, you can double up that yarn to double its thickness. I did this for many designs such as Starpath and Buffalo Knot Belt.

For scrap yarn crochet projects. Say you wish to use up as many leftover yarns as you can of a certain color range. They likely differ in length and thickness. The fun part is doubling up some of them to even them up and combine well in a project. I did this with all of my teal shades of leftover novelty yarns for "Scrappy the Draft Snake."