Phil became the lead singer in Then There Were Three. When they looked for a replacement for Peter Gabriel, Phil would demo the song the new candidate was about to sing. After dozens of potentials they decided Phil Collins was the best choice.
Of course Phil has a strong jazz streak in him that more songs like this, to their more commercial sound from the signature art rock classical feel. Tony Banks was classically trained and used to have a strong influence in the music.
I heard Tony let them go work with the Earth Wind and Fire horns for Paper Late, and some future songs (Ababcab)
Nobody goes under much for dentists like the old days ...
If you look for the band Brand-X you will find a Jazz band with Phil on drums, and some CDs he may sing, but they were virtually music only recordings.