[Avodah] Bracha after Haftara on Shabbat Rosh Chodesh

[Lisa Liel]

This bugs me every time there's a Shabbat Rosh Chodesh, but I always 
forget to ask about it after Shabbat is over.

On yamim tovim, we finish kiddush and the middle bracha of the musaf 
amidah with "mekadesh Yisrael v'ha-zmanim".  We also end the last of 
the brachot after the haftarah that way.  On Shabbat, of course, we 
end all three of those with "mekadesh ha-shabbat", and if it's 
Shabbat *and* Yom Tov, we end all three with "mekadesh ha-shabbat 
v'Yisrael v'ha-zmanim".

But on Shabbat Rosh Chodesh, we end the middle bracha of musaf with 
"mekadesh ha-shabbat v'Yisrael v'roshei chodashim".  And both kiddush 
and the last bracha after the haftarah end only with "mekadesh ha-shabbat".

Why the inconsistency?  I see why we say a special bracha in the 
musaf amidah, because that whole nusach that precedes it is special 
for Shabbat *and* Rosh Chodesh.  But why do we ignore it during 
Friday night kiddush and the bracha after the haftarah?

Lisa