I leave all 4 lines attached to the kite all the time. The drawback is that you need a bar and lines for each kite to do this. This is much faster and easier once you get it down. I took a while to work the bugs out. Basically, you can only get crossed lines if the kite turns inside out while packing or unpacking, or if the bar goes through the lines. When winding up, I start by winding the leaders in a figure 8 pattern around the bar as opposed to the bar ends. When I get to the lines, then I wrap around the bar ends in a figure 8. I would wrap everything around the bar ends, except there is not enough room - especially with the adjustment strap. My problems usually occured when I would wind all the way to the kite, and then flip the kite over to deflate, the bar would get airborn and flop through the lines. This is prevented by winding to within 20 meters of the kite, temporarily tying off far enough away from the kite to avoid the possibility of lifting or dragging the bar, packing up the kite, and then continuing to wind up the bar and attaching it to the outside of the kite bag using the velcro wrist leash. Half hitches on one side of the bar and the leash on the other to hold everything together. You can also pack the kite before winding the lines if you don't mind taking a few extra steps. The bar is very sneaky, looking for any opportunity to pass throuth a line during transportation, storage, etc. Doesn't matter where you store it, inside or outside the bag, just as long as it can't move.
When launching with an assistant, make sure they are holding on tight and give it some pulls, jerks, and flaps against the ground (the lines) and this usually takes care of it. If it is badly tangled, then I can walk the outside lines usually just part way to the kite and then try again.
When self launching, I have to unwind downwind of the kite, leading edge down and walk the outside lines all the way to the kite. A little extra time and steps, but still easier than attaching the lines each time.
If I have to deflate all tubes, I leave the center strut inflated, deflate all others, and role the kite up around the center strut, rolling toward the tips downwind, when I reach the tips, I deflate it and fold a couple of times. This avoids much flapping. I see many people folding or rolling each tip toward the center, but this twists the lines.
If I am in a location where I am not driving up or down in elevation too much, and if I have room in my vehicle, then I leave all struts inflated, so that next time I only have to inflate the LE. With a high volume pump, it just takes a few minutes to get on the water. Its not that I am in that much of a hurry, I am more interested in ease and convenience than saving a few minutes. But rigging and derigging is one of the negatives of both windsurfing and kiting and anything that can improve on this is a good thing. This is definately faster than rigging windsurf gear. If I want to hustle, I can be on the water in 5 minutes. I usually take a little more time just to be safe. Any one else out there leave all 4 lines attached?