Question: Both Isaac Slade and Elizabeth Fraser shared song writing and what other position in their respective bands or solo acts?

Context paragraphs:
The Golden Communion: The Golden Communion is the sixth album by Thighpaulsandra, released on September 4, 2015.  It marks Thighpaulsandra's return to solo work after nearly a decade of touring with Spiritualized, Elizabeth Fraser and Wire.  The album pulls from over ten years of recording sessions; as such, "The Golden Communion" boasts collaborations not only with Thighpaulsandra regulars Martin Schellard and Siôn Orgon, but also with John Balance and Peter Christopherson, the late founders of industrial band Coil.  Overall, the music presented contains threads of psychedelic and progressive rock, featuring orchestrations and extended pop music song structures not heard before on a Thighpaulsandra album.

Head over Heels (Cocteau Twins album): Head over Heels is the second studio album by influential Scottish rock band Cocteau Twins.  The album was released in October 1983 by 4AD, and was their first album as a duo of Elizabeth Fraser and Robin Guthrie.  It featured the band's signature sound of "Guthrie’s lush guitars under Fraser’s mostly wordless vocals" and is considered an archetype of early ethereal wave music.

Mysterio (album): Mysterio is an album by Ian McCulloch, released 17 March 1992.  This was McCulloch's second solo album since his departure from Echo & the Bunnymen in 1989.  The album features a cover of the Leonard Cohen song "Lover, Lover, Lover," as well as a guest appearance on the song "Heaven's Gate" by Elizabeth Fraser of the Cocteau Twins.  The album reached number 46 on the UK Albums Chart and number 39 on "Billboard"'s Top Heatseekers chart.

The Space Between Us (album): The Space Between Us is the debut solo album by Craig Armstrong, originally released in 1998 on Melankolic Records.  Elizabeth Fraser of Cocteau Twins contributes vocals to the track "This Love", and The Blue Nile's Paul Buchanan appears on "Let's Go Out Tonight", which is a rework of the song of the same name by Blue Nile.  The first track, "Weather Storm", is a reworking of a song by the same name which appears on Massive Attack's 1994 album, "Protection", to which Armstrong contributed.  Similarly, "Sly II" is a reworked version of Massive Attack's "Sly", also from "Protection".  "Balcony Scene" is a reworked version of "Time Stands Still," from the score of the 1996 film "Romeo + Juliet"; it contains elements of "Kissing You" by Des'ree, as well as a quote from the film.

Peter Koppes: Peter Koppes (born 21 November 1955) is a guitarist, best known as a founding and almost-continuous member of Australian independent rock band The Church.  He is a multi-instrumentalist, also playing mandolin, drums, piano, and harmonica.  He has also released various solo albums and various recordings with his group The Well (1989-1995.)  Koppes lives on the Sunshine Coast in Queensland where he also produces albums and conducts seasonal 'song writing' and 'performance for demo recording' short courses at Nambour TAFE, as well as offering private tuition in guitar, drums and song writing.  His daughters are Tatiana 'O' Koppes and Neige Koppes who have their own band, Rain Party  (formerly they played with The Kicks aka Bright Red).

It'll End in Tears: It'll End in Tears is the first album released by 4AD collective This Mortal Coil, an umbrella title for a loose grouping of guest musicians and vocalists brought together by label boss Ivo Watts-Russell.  The album was released on 1 October 1984, and reached #38 on the UK Albums Chart.  It features many of the artists on the 4AD roster at the time, including Cocteau Twins, Colourbox, and Dead Can Dance; as well as key post-punk figure Howard Devoto, who sang "Holocaust", one of two covers of songs from the "Third/Sister Lovers" album by Big Star.  The other Alex Chilton-penned track, album opener "Kangaroo", was released as a single to promote the album.  Two key songs were performed by Elizabeth Fraser of Cocteau Twins, including Tim Buckley's "Song to the Siren", which reached #66 on the UK Charts when released as This Mortal Coil's debut single a year before the album.  The song remained on the UK Indie Chart for almost two years.  Fraser also performed on "Another Day" by Roy Harper.  4AD would go on to release two further albums under the name of This Mortal Coil: "Filigree & Shadow" (1986) and "Blood" (1991).

Elizabeth Fraser: Elizabeth Davidson Fraser (born 29 August 1963), sometimes known as Liz Fraser, is a British singer, songwriter and musician from Grangemouth, Scotland, best known as the vocalist for the band Cocteau Twins.  She has a soprano vocal range.  She was described by critic Jason Ankeny as "an utterly unique performer whose swooping, operatic vocals relied less on any recognizable language than on the subjective sounds and textures of verbalized emotions".  Her distinctive singing has received much critical praise; she was once described as "the voice of God."  Her lyrics range from straightforward English to semi-comprehensible sentences (idioglossia) and abstract mouth music.  For some recordings, she has said she used foreign words without knowing what they meant – the words acquired meaning for her only as she sang them.

List of garage rock bands: The following is a list of notable garage rock bands.  It is not exclusive to collective bands, but also includes solo acts who have created music in this style (usually backed by accompanying musicians).  The list features artists from the US and Canada, but also includes similar acts from other countries. <ref name="Bangs (Psychotic Reaction/Troggs)"> pp. 54, 57, 61, 64, 101</ref>

Cocteau Twins: Cocteau Twins were a Scottish rock band active from 1979 to 1997.  The original members were singer Elizabeth Fraser, guitarist Robin Guthrie, and bassist Will Heggie, who was replaced by multi-instrumentalist Simon Raymonde in 1983.  The group has earned much critical praise for its distinctive ethereal sound and the distinctive soprano vocals of Fraser, which often abandoned recognizable language altogether.  They were associated with the UK label 4AD for much of their career.

Isaac Slade: Isaac Edward Slade (born May 26, 1981) is an American musician and the lead vocalist, main songwriter, pianist and co-founder of Colorado-based rock band The Fray.

Supporting paragraphs: Isaac Slade Elizabeth Fraser
Answer: vocalist