The adjuster screw does touch the worm.
The worm gear has four pieces. The outer worm, that is mounted in the left side cover. The inner worm, threads into the outer piece. Has an arm that the cable hooks to.
Inside the inner worm is the adjuster screw and a ball bearing. The ball bearing allows the push rod to spin while the adjuster screw stays still.
When you adjust the screw, what you are adjusting is the freeplay between all the parts between the adjuster and the pressure plate.
At this point you want minimal play so as you pull the lever you get the maximum amount of pressure plate travel.
If this adjustment is too loose you will have clutch drag, hard to find neutral and shift.
If you have this adjustment too tight the clutch will slip.
So when you turn the adjuster in, clockwise, when you just start to feel resistance, this means you have eliminated all free play. The turning back 1/8 turn gives you just a bit of free play. You need just a bit of free play to prevent slippage.
Once you get this adjustment set lock it down with the nut. Now up at the lever, you set 1/8 to 1/4 inch freeplay there.
I do it buy holding the cable with one hand, working the lever with the other. You will see the cable move in and out of the cable adjuster. Adjust to get the 1/8 to 1/4 inch of cable movement.
Here the same applies as down at the worm. To loose and not enough travel, to tight and you get slippage.
As the engine warms up the cases expand at a slightly different rate as the push rod. This can make the lever adjustment change slightly.
I like to adjust things cold, once warmed up check them again to see the difference. Any adjustments needed at warmed up should be done at the lever. If you do the worm adjustment hot, it will be to tight cold.
Leo