imaging and speaker placement with tv in center

I have a long room 27 wide by 15 deep which is my music room (8' ceilings). I have my speakers 10 ft apart with the stereo cabinet (CWD lowboy) between them and slightly recessed from the speakers which are 26 inches from the back wall. My 36 inch behemoth Proton tv sits on the lowboy. The imaging is great, with soundstage larger than the speakers and at times depth farther back than the wall itself. I get pinpoint imaging that seems to eminate from where the tv is in the centered position.

The speakers are Von Schweikert Vortex Screens (somewhat similar to the VR4's) low driver 28 " off the floor and mids and highs mounted in separate cabinet section above. These speakers have a transparent nature to them, they sound like sound eminating in space, with no hint of cabinet coloration - even though they are 4.5 foot tall monsters. By walking around the speakers one can determine that they do not radiate sound off axis 90 degrees so I don't see that TV between them would interfere with the image, as it's slightly recessed back from the side axis of the speaker. Sometimes the cabinet doors are open for ventilation which could affect the imaging a little (I can always take these off, no spousal unit or gf to confound things cosmetically)

I am in a near field setup. Speakers 11 ' from me and 10 feet apart, 28 inches from speaker backs to the wall (speakers 14" deep). Speakers toed in an inch. My couch is against the back wall, so no back wall reverberation. The side walls are 9 and 6 feet away for cosmetic and traffic flow reasons.

I use the system primarily for music, but it also serves as a great two channel movie setup (not into 5 channel HT).

I have three questions
1) should/does the tv disctract from the imaging?

2) how far from the backwall?

I checked the archives for speaker placement and saw the Cardas setup. His depth to backwall calculation of width x .447 seems ridiculous or only applies to setups where the speakers are along the short wall. For my setup 27' x .447 says the speakers should be 12' off my back wall, or 3 feet from me. Or 6.7 feet if the width is really the short wall distance for calculations, still well out into the room

My setup seems to be very nice from an imaging standpoint, but I would like to fine tune things if possible. I don't have any special room treatments - carpeted, some posterboard music posters on side and back walls

3) does anyone have room placement formulas or recommendations for placing speakers on the long wall like my 27x15 setup? the cardas setup doesn't seem to hold here, except the equilateral triangle end

thanks

Tom