On my Gemini I lead everything (and I mean everything from cunningham to vang) was lead aft. Mind that was on a stable platform where going forward was a simple stroll on a mostly flat deck. It was still a 8 foot walk across the cockpit to get to the halyard and reef lines
(the up/down bit was to port, the in/ out bits were at the helm to starboard).
For me it was about instant sail tweak ability and ease of use.
The mast had no self tailing winches
and it was actually more cost efficient to add six blocks, two deck organizers and two 3 line
clutches than it was to replace a single winch
with a ST. I used Garhauer throughout.
The main was fully battened on batt cars and dropped right into the stack pack that my wife made, no muss, no fuss.
On the Irwin 38 CC, nothing is lead aft. Jury is out on what I'll be doing, it's a center cockpit so the dynamics change considerably.
The main reason I can see not to lead lines
aft is if you are a performance racer - then the extra line
used for the halyard provides more stretch and therefore induced sag to the luff. You can always crank it out, but it will come back in a puff.
The other reason not to lead aft is the extra 'weight work ' caused by the friction induced by the extra blocks and organizers.
That's a highly individual call that depends on what gear, how big the sail is etc..
If you are leading aft you are likely not a racer (see the stretch issue above) - so you might as well look at making your halyard a 2:1 ( via a light weight block at the head and a hard point connection at the top of the mast) - a lot of the big catamarans do just that. It's a lot of line in the cockpit, but then they have a lot of cockpit. Using low stretch lines available today makes it possible.
A lot of posters have said the viability of leading the halyard aft depends on the reefing - I don't think that is as important, it's certainly not a show stopper - especially for a day sailing boat. Here's why:
If you are going to lead the halyard aft you can just as easily lead the reef lines aft. Put a line through the reef grommet at the clew and rig
a block as a down haul - poof, no requirement to go forward to attach the grommet to the horn
. Mark the main halyard so you know how far to lower the sail - or go with a infinitely adjustable reefing set up.
The back of the sail is right there in the cockpit with you, just stand up pull / fold and tie. Done.
Okay, the last reason not to lead aft - through deck penetration and toe stubbers.
It's there, it is a real reason, get over it and do it right, and mind your toes.
Once you put an organizer in you'll start thinking of all the other things you can lead back so it's right to hand at the helm. Think cunningham's, vangs, outhaul, lazy jacks
Once you have that you can tweak the main to your hearts content, all while staring at your .0001 knot sensitive GPS
speed so you can instantly see the effect of your shape change.
You are far more likely to adjust the sail controls if the means to do so are immediately at hand. Tension of the halyard is one of the main controls - yet most folks raise the main and never touch the halyard until they drop the sail.
We can't all sail on a 10 person crew wave thrasher, doesn't mean we can't have the ability to tweak and play - isn't that why we are out there?