Rufous-tailed Scrub Robin - Two different species?

Further to my post on Rufous-tailed Scrub Robin I have receied some interesting information that some people treat Rufous-tailed Scrub Robin (Cercotrichas galactotes familiaris) as a separate species from (Cercotrichas galactotes galactotes). Lee Evans states that he treats them separately with the birds occurring in Saudi Arabia know by him as Eastern Bushchat (Cercotrichas familiaris syriacus). This is based, mainly on the noticeable differences in vocabulary, although they are also very different in plumage to birds he calls Western Bushchat (Cercotrichas galactotes galactotes), being much paler and greyer on the upperparts and very pale on the underparts. This paleness contrasts strongly with the rufous-red tail and upper-tail coverts, with the tail being noticeably shorter with less distinctive white tips and has more obvious black subterminal markings. They also have a more striking head pattern, highlighted by a more prominent white eye-stripe, darker lateral crown stripe, darker moustachial stripe and a larger pale spot below the eye. Western Bushchat breeds in Portugal, Spain, Morocco, Tunisia, Algeria, Libya, Egypt, Sinai, Israel, Jordon and Syria where it is a migrant breeder. They winter in the Sahel region of West Africa (where the form minor is also resident). Eastern Bushchat is a migrant breeder in Greece, Turkey, probably northern Syria and Lebanon, Turkmenistan, Afghanistan, Kazakhstan, Iraq, Iran and is an uncommon but widespread breeding species in Arabia (ABBA Atlas - Jennings 2010). They winter in Northeast and East Central Africa. Whether you agree or disagree with this interpretation, it is an interesting point of view with good details of the reasoning behind it. The photographs below show the plumage features that Lee mentions and I thank him for sharing his knowledge of these birds with me and also thank Brian Small for range information. This information came about from a mystery bird thread at the Surfbirds Forum found here