Oldest Question In The Book.

I've never really thought of it that way. Now that I think of it I realize how inefficient that really is

10--lava can kiss my water bucket.

I personally mine like this (O, is mined; whereas X, is not strip-mined):
XOXXXOXXXOX
XXXOXXXOXXX
XOXXXOXXXOX

I tnt it all.

Exactly. But if you're at y = 11, you can pour the water bucket and the lava will be under your feet at the floor level, you don't have to mine any obsidian if you don't want to.

Personally I strip mine either from one outpost to the next, or go for a few hundred blocks and dig another one next to it in the opposite direction. I usually spread them out by a dozen blocks or so, and I think that's the most effective, as you'll never have veins running into the other mine.

I dunno... I've never had the need to determine where I place my mines. I just dig in a straight line and take whatever I can get.

I take a cave, pack it with TNT and blow the place to smithereens. Usually results in death. Do not try at home.

You guys been talking! Glad to hear that this thread interested some of you! Also, seeing that people have been answering honestly in the poll is such a mood uplifter! I want to hear more opinions, and maybe some experiments with the layers, like how much lava have you encountered at a particular height.

At 6 I rarely encounter any lave. I don't mine through obsidian though. I just block in the lava. Especially if I plan on digging out the area for a build. Its become habit so I always do it. I generally save a pool for smelting though. Mining in one direction is ok but if you plan on collecting a lot and being there for a while its more convenient to strip everything around you. If you are going to be an hour or two you might as well use the outposts and ender chest to your advantage. I'm an xhills junkie though so strip mining is the way I go. I will mark out the biome border and set up a beacon. Only get the area with emerald ores. Dreacon will obliterate the while mountain from surface to bedrock. I stay down low. I don't even take the stone with me. That's what the economy is for, so I can buy dreacons and maximize the efficiency of my time lol.

Here's a map of how I mine.
S - 13
A - 12
A - 11
S - 10
Except that I also do peepholes every 4 blocks.
S SSSS S
AAAASS
A SSSS S
S SSSS S
There's 3 blocks between each peephole, instead of 2, because diamonds are likeley to spawn in viens of 2 or more than as just one block. And even if there's only one diamond, it's even more unlikely that you will skip it.
Because of this, I space my brances like so.
S SSSSS SSS SSSSS S
AAAAAASSSAAAAAA
A SSSSS SSS SSSSS A
I also use fortune 3 or silk touch on my ores (silk touch -> fortune 3 later), to get maximum profit from them. A quick 20 minute trip (with an efficiency 3 digging pick and fortune 3 ore pick) got me 20 diamonds using this method. Happy mining!

You explained it better than I could. I was gonna look for a youtube video to explain it when I was on my comp. That is exactly what I do when I'm not in xhills but instead of having 13 blocks between each shaft I have only ... purely for OCD reasons, 9 blocks inbetween. Mineshaft every 10 blocks is just easier on my brain lol.