Toe in is crucial

I'm the rest of us, and I don't obsess over the smallest tweaks, most of which are simply conduits for confirmation bias. However, toe in can indeed make all the difference. Like, @hilroy48, i blue-taped the placement grid for my Spatial Audio M3's and found that even 1/2" made an audible (though not huge) difference. And I'm still dubious about how Reference 3A advises NOT to toe in my de Capo's. Yet anytime I do toe them in, the sound muddies up.

You’re absolutely correct. Proper speaker toe-in is absolutely critical. In my room, it took me forever and a day to finally get my speaker toe-on spot-on. It took a lot of time and patience, but once I got the speakers toe-in just right, I began to experience the kind of audio nirvana that I was seeking.

Proper toe-in is definitely one of the critical basics of speaker placement. I have the same speakers as you. Getting it right took me a long time… I was not in a hurry. Purchase of speakers… upgrading components and cables took a year until I finally got to fine tuning my speakers. I found a gradual change in the soundstage from having the beams crossed behind my head to no toe in. In my venue, no toe in gives the widest / deepest soundstage without loosing the central image, where the speakers disappear. I was surprised since the recommended toe in is to have them cross behind your head. Just shows you have to do your own place.

I have had speakers (electrostatic and ribbon) where 1/8th an inch made a big difference. In my room the Sonus Faber Amanti change their presentation gradually. 

This is what I use:https://www.amazon.com/gp/product/B0863RK1KX/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

By placing it on top of the speaker along the inside edge, I'm able to fine tune the hight as well as direction.  I'm sure ton's of people use these.

Toe in changes the speakers relationship to the room as well as the listener. These variables are not easy to account for. So, it is very much a trial and error undertaking. First it is important to deal with first reflection points on the side walls in particular. I always start with the speakers perfectly perpendicular to the radius aimed directly at the listening position then if the image is not well focused start gradually reducing toe in. @ghdprentice Because line sources radiate in a figure 8 fashion, they send no energy towards the side walls. They should always be aimed directly at the listening position for the best image. As you note, reducing toe in changes the sound in a much more dramatic fashion, usually for the worse. Any brightness should be handled electronically. On the bright side the side walls do not require absorption. Only the front wall behind the speaker needs absorption. SALLIEs are the best. You can see them on my system page.