My opinion is that relative phase is preserved on both LP and tape as well as other two channel media.
A stylus works in that the orthogonal grooves on a record (left side and right side) create orthogonal vibrations of the stylus (Up Right to down left) and (Up left to down right.
Tape may have more air because of hiss and/or better channel separatiion. Hiss can help you hear things BELOW the noise floor and channel separation on an LP is lousy anyway.
A stylus works in that the orthogonal grooves on a record (left side and right side) create orthogonal vibrations of the stylus (Up Right to down left) and (Up left to down right.
Tape may have more air because of hiss and/or better channel separatiion. Hiss can help you hear things BELOW the noise floor and channel separation on an LP is lousy anyway.