Its faster to have a seperate tack/halyard. You can pull the tack before the offset/windward mark that way. With the combo system you're pulling a bunch more line.
-The way mine is set up the tack line is cleated with a Spinlock underneath the tramp and mounted on the backside of the front beam. I drilled a hole through the top edge and tied off a piece of tiny line. The other end of the tiny line goes under the tramp and comes out through a grommet where it is tied off to a ring.
-The spinnaker halyard comes down the mast, through a cleat, then down to the front beam where it runs through a eyestrap, then through the ring that is connected to the spinlock. The halyard then goes through a grommet and underneath the tramp where it goes through the two rings attached to bungees, one of which is the tail end of the tackline. Then it comes up through the tramp, then through a block, then through a hole in the tramp, and onto the spinnaker patches. Behind the block, and forward of the grommet where the halyard comes topside is where you grab it for dousing.
When dousing you just pull the halyard from the tramp, it releases the both the tack and the halyard at the same time, or you could grab it at the cleat to leave the tack cleated. All the benifits of the simple dousing combo line, but you can set the tack seperatly.
The bulk of my halyard is just cover/no core as well, with a section of dyneema above the cleat to the head. Its a copy of how Robbie Daniel's boat is setup, he made the halyard/tack line for me as well.
Don't forget that the doubling block can cause issues as well, whether its mounted on the mast, or the spinnaker pole.