Tweaking Your Speaker Placement

Kidding aside, yes, I think 1/8" increments is pretty severe, but I've done like 1/2"  and believed I could discern a sharpening of the sweet spot.

@tony1954 

I have 240 pounds speakers on iso acoustics. My solution is having them resting on a butcher block. Whether on hard surface of carpet, the butcher block can be moved by pushing or pulling it at the base accordingly. It will move even a 240 lb speaker, though it requires good hand strength.

"Depending on the speakers an 1/8” move in the right way can have a significant impact."

You have realised, of course, that it's a figure of speech -- not a literal statement? Kudos, however, for creating a discussion out of it!

60 lbs would be a piece of cake.

Laser measures are super handy for this process. 
 

I too use IsoAcoustics feet and placed them on thin slippery material so that I could tweak positioning. This was how I discovered how much difference they can make. When they no longer grip the floor, some of the magic disappears.