Do you really use the formula for speaker placement?

Thanks for all of your input. I first watched and went by the advice provided in the Youtube video. It was a different approach in that it asked you to start with the speakers literally next to you and move them to the wall. The wisdom is that there would be a point where the speakers disappear. They did. Then the instruction was to move them left/right by about 8 inches. This provided a good result. Then, I tried the Sumiko Speaker Set method. Interesting. It starts with finding the place in your room where the bass comes through the best. So, it starts with one speaker only, and the setup is predicated on excellent bass. You'd think the placement would be right next to the front wall. I am much more interested in imaging and the soundstage than a loud thump. So, the place for the left speaker turned out to be close to the placement for the youtube video method. The Sumiko Speaker Set method then went into seeing if the sound stage was "slanted." if one speaker is too loud, move it back, etc. Then, it went into toeing the speakers. I know we've all done this but I thought I was  no-toe guy until I finally understood that no-toeing can produce a thinner sound. I like a wide sound stage but I understood that I was trading off a richer sound. Then the methodology went into slanting the speaker a little up, which I'm not able to do. Takeaway: I knew speaker placement was important but I was surprised how big a difference very small distance changes make. Obviously, sound is made of waves, so distance makes a difference. I was just surprised by how much. I liked the concept of "slant," which I'd not heard before. In the end, the Sumiko method created a much more 3 dimensional sound stage. both methodologies arrived at the same distance from the front wall. With sumiko, the speakers were about 10 inches further apart and toed in. Sumiko seems to account for the room's acoustics more than the other method. Anyway, the differences were noticeable, the improvement was free, and it was a fun exercise. Thanks for the input.

When following the Youtube setup, were they perfectly equidistant with L and R toed in symmetrically the exact same amount? If not then how different were the distances and angles?

How exactly was the final Sumiko setup different? 

You're right about tiny distances making a big difference. So what exactly were the differences?

@millercarbon The youtube setup had the speakers equidistant. Frankly, it never occurred to me before the Sumiko Method that speakers would be anything other than equidistant from the listener--the normal equilateral triangle rule. And the youtube didn't mention making the toeing different. Again, I just assumed the toeing would be the same. That's why the "slant" idea was kind of a shock. I haven't experimented with unequal toeing. I assumed you'd want them toed the same to make the sound in the center, like voices, focussed. but now that you mention it, it takes 2 seconds to experiment. I don't know if anyone has tilted their speakers. I can't do that but wondered if that small change made a big difference.

@squeak_king. Thanks!

The reason I ask is the Sumiko setup has you moving one "anchor" speaker for bass and then the other, and then making lots of little adjustments all by ear. Nothing about symmetry, nothing about equidistance. Since I know equidistance is essential for imaging, and since a tape measure is way faster and more accurate than trying to do this by ear, I am curious how close to equidistant you got using that method. 

The next question would be if you did measure, then tweak just the one thing to be equidistant, does that improve the Sumiko setup. Because I know for sure it will, just curious if you tried.