To figure out which one to use, based on the stitch and row gauge of your swatch (mine is 34 sts and 50 rows to 10cm/4 in.) 9 cm for half the width of the neck is 30 stitches. Using the EOR option means the neck needs to be shaped over 60 rows which would be (60 divided by 5.0 = 12 cm) and that was deeper than I wanted. Using the second method of 40 rows results in an 8 cm drop. Going with the 40 row plan, look at the row count of the top of the shoulder and work back from that to find your starting point for the vee. I found a way to get the chain stitch going all the way from top of one shoulder, down the vee and back up to the other shoulder:
|side of the vee, to be added|
CAR. Set to hold. Bring left of 0 to HP. Knit, wrap, knit (KWK). At right of held sts, hold [1 st, KWK, 2 sts, KWK] 10X, to 30 sts at right of 0 in hold. This should be done about the time the shoulder needs to be shaped. Leave the neck sts in hold and complete and remove the shoulder without wrapping at the shoulder side. CAR. Return left side to UWP. Main yarn, K1R to left. Shortrow the left side of the vee in reverse and do the same, finishing off the shoulder. Once that is removed, there are 30-0-30 sts in HP and there might be an inch or so from the last needle held up to the top of the shoulder. That is part of the neckline. Stretch it our slightly and hang on 3-4 ns at edge. Repeat on other side so now there is 34-0-34 ns. Manually knit loose row over all and chain off.
Making the first piece, in tobacco brown, I added some shortrowing just above the hemline to compensate for the lack of a bust dart. This might sound really weird but, because I did not want it to show, I spaced it out with two plain rows between each shortrow set like this: K2R. CAR. At side opposite, hold 15 sts, knit, wrap, 2X. Bring side opposite back to UWP, knit, wrap, 2X. K2R. At side opposite, hold 25 sts, knit, wrap, 2X. Bring side opposite back to UWP, knit, wrap, 2X. K2R. Repeat this again, increasing the amount of held stitches by 10 sts each time, so I was adding an extra 10 rows at the centre but spread out so you didn’t get a line from the wraps of the shortrows. It actually works very nicely.