Here’s the next article about the relatives of Twincrease. It describes existing Double Increases, and examines their true nature. It is an attempt to categorise all Double Increases.
You’ll also be introduced to a new addition to this family: it’s a totally symmetrical Double Increase made from one stitch. It is called T-increase, because three stitches line up horizontally, resembling the letter T or even a Trident. The full name could be Trident-increase.
Here is a full tutorial with photos, videos and chevron samples.