Taut-
Because tiny leading edge kites don't keep their shape, bridle or no bridle, fifth or no fifth!
There were 2007/ 2008 kites with leading edges that were too small, and there are still 2011/2012 kites designed that same wrong way, in my opinion.
I don't mean, as small as you can make them and still keep a rigid kite, I mean too small.
Doesn't matter if you have a fifth line or a ladder bridle, they're still soft and that leads to crappy performance in real life, if not on paper.
They fold at the middle or at the tips or both, when you send them for a jump, they invert, they also don't work well for big men or in really high gusty wind.
I would name the few examples I know of, but I would start a war, and I am not up for it today.
But let me give an example of a really big fat leading edge kite that works just fine.
The Wainman kites, may not be everybody's cup of tea but they perform pretty well for the majority of of what most kiters look for today.
They are not race specific and they will not boost/float like a few of the higher aspect five strut boost monsters, but they turn fast, feel direct, surf very well, do freestyle pretty well, are very stable and gust resistant, have huge range and relaunch great.
On the other hand, the last three 2011/2012 kites I flew with an overly small leading edge were lousy kites, I would not fly them if I had a garage full of free ones.
For me, a five line kite gets way more complex when I dump it in the waves, so there is a difference between a five line and a good four line kite, in my opinion.
There are four line kites that feel pretty darn direct, ..with and without bridles and the dreaded pulley..the Fuel, C4, Judge and Rabbit being four examples of different ways to do a four line kite well, three of which can be flown with or without bridles or pulleys.
I'm not saying five lines kites are no good, the non bridled C kites (which seem to need it, other than Fuel and Judge C kites) are getting great reviews and lots of kiters are buying them and like them a lot.
I'm saying I don't see a need for it on a Rebel when the Fuse exists, SLE types like those should not need five lines, in my opinion.
Ceasar -
The sun shines 300+ days a year here and it's hotter than hell, it is not hurting my black kite.
If I kited every day and expected it to last five or six years, then yeah color might be a consideration.
The wind will kill any kite that gets left for long periods on the ground flapping in the wind regardless of color, the sun will help, but it is really the wind mostly.
All dark colors absorb light, dark reds, dark blues, dark greens, chocolate brown....whatever.
Never seen a kite die faster based on color.