Nairobi Senator Edwin Sifuna reluctance to join or form coalition with parties of established seasoned politicians like James Orengo, George Natembeya and Babu Owino might a lesson learnt from the late president Mwai Kibaki tribulations with the National Rainbow Coalition [NARC].
Established seasoned politician Charity Ngilu was the chair and leader of NARC while Kibaki was it presidential candidate in 2002 first mult-party General Election. Despite Kibaki winning with landslide on NARC ticket, Charity Ngilu denied him a chance to run on NARC in 2007 second General Election. This set Kibaki back to drawin board and hurriedly crafted a new coalition, the Party of National Unity [PNU] and run on it and controversially won with slim margin.
So, I opine that why Senator Edwin Sifuna scouted for the party without established politicians and settled on The Equitable Party [TEP] and rebranded to Linder Mwananchi.