Control lines
Those control lines that lead aft to the cockpit over the cabin top and under the traveler, etc. were put there for a reason. The reason being to keep your cockpit perpetually cluttered with a tangled mess of lines.
Actually they are led there so that in theory at least, you don't have to leave the safety and security of the cockpit to do things like adjust a halyard or reef the main sail. Unfortunately on my E38 it's a thought that never got completed.
My main halyard runs aft to the cockpit and the leach reefing lines are run aft to the cockpit so reasonably one would think that you could reef from the cockpit. Wrongo. The crew must still go forward to the mast in order to hook the reefing grommets to the reefing hook at the tack end of the boom. I would need still another pair of reefing lines led back to the cockpit to reef the new tack from the cockpit. Also with my dodger/windshield arrangement, the crew must go forward of the cockpit canvas to adjust the traveler.
Fortunately, the winch clearance was considered when the bimini/dodger was built so I have good clearance on two of the three cabin top winches with the windshield rigged. Without the windshield, all three can swing full circle.
I suppose too that when racing it helps keep crew weight more centered in the boat (fore & aft)... maybe.
With all the drag induced by leading lines aft through a gaggle of blocks, my main is a pain to raise. I find it much easier to just go forward and jump the main halyard by hand while wife takes up the slack. I winch the last foot or so for tension.
When racing we station the main sheet trimmer on the companionway steps where the self-tailing winch is in a comfortable grinding position. From there one can see the mainsail and reach the traveler controls. But if we were serious racers, that's a body I'd rather have on the rail.
I'd be interested in seeing a better idea too.