Front speaker placement, trying wider placement.

My room is 12' x 16' and I started with the equilateral triangle positioning. It was almost perfect from the beginning. I only had to adjust toe-in, rake angle and move speakers a couple of inches away from wall.
Then add some absorbion in the corners.

Some speakers are designed to sit in the corner, but very few.

If the speakers are good enough a wider stance makes sense, and seems to be working better at this point.  
Sound fills the room more broadly, stereo twp channel sound has a nice projection from center. 
I think some are abit neurotic about toeing in and eqidistant speaker placement.  

Putting speakers in corners is not for me. However,if it works for you,then set them up wherever they sound best to YOUR ears. You are going to have to trust your senses no matter what us keyboard jockeys say. Who am I to question what you hear? 

Many like to place mains on each side of flat tv. Too me this seems to limit spread of sound throughout the room. And limits so called sweet spot to a one chair position. If u are are hermit this may work but many coexist with others and spreading the wealth seems more comfortable.

problem is mains are so damn heavy that its tough to move them around. At least b&w speakers have ‘wheels’. Also speaker cables can be too damn short. I got 12 footers.

Part of it is the compromises you are willing to make. Most of us want the best possible sound as system owner. So widening the sweet spot will reduce the sweetness of the spot. Having a reflectiveness of a flat screen will confuse the imaging. While the equilateral triangle is a rule of thumb, my experience is that optimal sound is achieved about there. Unless, you are running some odd kind of speakers like Ohm Walsh.