Hi, Ted,
Herewith, a post in which I pick some nits and attempt to prove a point using completely inadequate photography.
A great while ago on the Heirloom Knitting list there was a discussion about the nature of paired increases and decreases, which arose from a statement on page 38 of Sharon Miller's book, Heirloom Knitting: A Shetland Lace Knitter's Patterns and Workbook, in which Sharon states that the knitting of paired increases and decreases really only applies when working with thicker yarns. For those of us, say, working with gossamer merino (as a random example), Sharon suggests that the decreases could just as well be worked as a k2tog, "without affecting the finished appearance after dressing."
This resulted in a bit of a debate, with no definite resolution, as I recall. Some knitters were perfectly happy just working a k2tog, others felt it was important to still work the paired increases/decreases, no matter what the weight of yarn.
(As an interesting aside, this very thing came up on Marilyn's blog recently -- scroll down to the entry and comments for February 21st.)
Well. Now. I've been mulling this idea over for close to two months now. After I'd worked about 20 repeats of the edging, I decided that maybe I should have thought about this before I'd actually started working the edging, but there we are.
So what I did, I cast on with my Original Crappy Yarn (TM) and worked two full repeats of the edging. In the first repeat, I used paired increases and decreases. For the second repeat, I used k2tog for all of them.
An interesting thing happened.
It took me fully TWICE as long to work the second repeat as it did to work the first one. I can probably explain this by saying that I was likely in a groove with the paired increases/decreases at that point, so switching gears slowed me down. But I did find it interesting that something that theoretically should have been faster instead slowed me down considerably.
And though I've been trying to convince myself that I really, really can't see a difference, well, I can.
Here's where the hapless photography enters the, er, picture:
The arrow marked "1" points to a line of k2tog decreases.
The arrow marked "2" points to a line of paired decreases.
For the life of me, the "1" is holier than the "2".
Okay, okay. I know that I'm trying really hard to show you this, and I'm photographing it on an angle, and really close up and whatnot. But I'm telling you, even before I blocked it, I could see that difference.
So what does all this mean? Well, probably not much in the scheme of things. We could apply the galloping horse rule -- if it can't be seen from the back of a galloping horse, it doesn't matter how you work the decreases. And that's fair enough.
It probably also means that I'm more anal than I previously suspected. Damn it, I need to work those paired incs/decs!
But what it also says to me is that it's really, really important to try this out before you get knitting, to see what happens. I can't help thinking about the structure of knitted lace, with pattern worked every row, and how the only structure it really has are those lines made by the increases and, more importantly, the decreases. If I were to choose, based on my sample, I'd say that the paired incs/decs give my lace a definitely crisper line, which I very much prefer.
And that, frankly, is enough for me. As always, YMMV, and make a swatch. You, know, before you start knitting.

Maybe you are more anal than you thought or maybe you aren't. What IS true is that you are the boss of your knitting so you do whatever floats your boat.
I can see two things in your picture:
1--yes there is a difference in the structure of the decreases
2--BUT the decreases zig zag back & forth in what looks to me like the same way so the net effect is the same.
So if you like one way better and it's faster then everyone else can just stick their advice, including me! LOL
PS: For crappy yarn that edging swatch looks pretty darn good!
Posted by: Aarlene | March 01, 2006 at 06:41 PM
And now I'm thinking that "mirrored" or "reversed" is probably a better way to explain this.
Sigh.
I think the swatch looks good because I wasn't afraid to block the life out of it, being Crappy Yarn and all. I suspect I'll be more timid with the Actual Shawl.
Posted by: k | March 02, 2006 at 08:35 AM
If it's any help, Katherine, I decided to be ye olde Purist with the Melanie shawl and I'm working my decreases as charted rather than just k2tog.
I'm not sure that with garter stitch it really does make a noticeable difference. Sharon may be right--once dressed, it probably won't make a noticeable difference. And I'm not able to see much from your picture. However, I sleep better at night knowing that I'm doing the mirrored decreases as charted. You can ask Ted. I angsted over this and had problems with it. Now I'm rolling right along. However, I did use his suggested sl 1, k1, psso in place of k2togB and I think he's right--it's much faster and easier to do when dealing with either knitted lace or lace knitting.
Posted by: Mar | March 02, 2006 at 10:18 AM
I like the paired decrease / increase one better. And strangely it's not for the holes! It's for the solid stitch that is between the two.
The one for the paired looks nice and even. The one the k2togs looks uneven and gappy. It seems to go in a short stitch / elongated stitch pattern. The paired one doesn't do that.
Looking good! Have fun knitting, time to get back to work for me.
Posted by: Danny Ouellette | March 02, 2006 at 11:21 AM
"I sleep better at night knowing that I'm doing the mirrored decreases as charted."
Yup. That's pretty much the bottom line for me, too.
Posted by: k | March 02, 2006 at 12:06 PM
My computer is in the shop: I hope it'll be back tomorrow or Wednesday. Will write a real reply then.
Not having a computer, of course, I had lots of time for knitting on the weekend and got about 15 edging repeats done. Of course I have a fabulous ache between my shoulder blades. Whodda thought I'd need to train for knitting?
Posted by: Ted | March 06, 2006 at 01:56 PM
Wow, you are doing such a beautiful job. Miles and miles of lace is right. I tip my hat to you. Your lace is wonderful.
And you are right. I have done the K2T on every decrease and I just don't think it 'feels' right to me. I am not sure how it looks after blocking but I have to go with my gut. I will continue to do it the old fashioned way.
Posted by: Junieann | March 07, 2006 at 04:56 PM