Symbiosis is a physical association between two different organisms whereby both benefit from the relationship. Associations where both organisms gain are then described as a form of symbiosis called mutualism.
His [Raila] political association with Kanu in 1997 where he saved Moi from a no confidence vote by rallying NDP MPs to vote with Kanu during the Orengo motion was one symbiosis for he got prime cabinet post. The one [association] with Kibaki after the 2007 post election violence to aid a weak PNU side in parliament was also symbiotic one for he prime minister post.
But the one for former President Uhuru and now President Ruto fit the bill of mutualism association. For all gain and above; stabilizing country Kenya from political turmoil which will ultimate place Raila a rack of stateman in my view if historians will fair in their analysis.