Winter is coming, both for Game of Thrones fans and for non-GoT fans. So it is time to practice knots, but hopefully, (k)not a hangman's knot. It is also time to revisit old discussions, and hopefully broach subjects with a new prespective to warrant new consideration. I know the prevailing wisdom is that 6mm accessory cord is the standard (if one is using nylon cord), and for longer rappels, esp. when using retrievable anchor systems, 3/16" dyneema cord has its place. I want to restrict the discussion to retrieving a 300' (or thereabouts) rope. I have attached a picture (hopefully it will print out for inspection) of three different sizes of accessory cord: 3mm, 4mm, and 5mm, as one moves from left to right. I am not sure of the rope brand in each case, other than the 3mm is definitely Blue Water accessory cord (thrown in as an extra in an order). I don't understand why either 3mm, 4mm, or 5mm cords aren't also utilized as accessory cords for rope retrieval. The two basic considerations that come to my mind are 1) rope weight (& bulk); and 2) ease of handling. Let's consider each in order. 1) rope weight -- always an issue with long approach hikes, and also with retrievalable anchor systems (to reduce the pull weight would exert on a fiddle stick, smooth operator, etc.). The accessory cords pictured above all weigh less than 6mm cord, so they would seem to win the weight battle. And of course, they would be less bulkly to carry throughout a canyon. At the same time, 3/16" dyneema is the clear winner, being lighter than all the nylon accessory cords and exerting miniscule weight on retrievable anchor systems. 2) ease of handling -- larger cord is easier to handle, and less prone to becoming tangling into a rat's nest. This would favor 6mm accessory cord over the smaller sizes. This is where I think 3/16" dyneema may have a weakness (though I don't own any). I did see a youtube video once that made me concerned about dyneema cord becoming (hopelessly) tangled. I assume that the expert canyoneers/rope wrangers on this forum have developed advanced rope management techniques with dyneema, thereby neutralizing this criticism. But having to develop special rope techniques may tacitly confirm that small dyneema cord must be handled with extra care -- or else. I would think that 3mm thru 6mm nylon accessory cords is easier to handle, and one might prefer the smaller sizes to reduce weight (as compared to 6mm accessory cord). Please discuss.