Sleeving of high performance kite lines like climax PROTEC or Dyneema is recommended because each knot in a line is a weak spot.
If you tie an ordinary knot, the strength in the knot is reduced by about 50%.
Using a Lark's Head knot the strength is reduced by much less.
If in addition the line is protected by a sleeve the strength in a
Lark's Head knot is only reduced by 10 to 20%. High performance lines like climax PROTEC area also very slippery. If the line isn’t sleeved at the ends, the
line is difficult could slip through the knot or eventually cut through itself.
Using a different coloured sleeve or mark on the left and right line makes
Because of their smoothness Spectra and Dyneema if not sleeved are
difficult to knot.