The name game

Parshas Hashavua

מטות ל"ב: מא-מב

The Chasam Sofer (Shu”t E.H. 2 :  18) writes that We don’t  find Yaakov to be called by both names at the same time.

We also don’t find in all the names of Tanach, Shas and early Poskim*, someone to be called by two names.

Naming someone with two names is a new phenomenon that didn’t exist in the olden days

Harav Izak (Yitzchok) Ausband zt"l (R.Y. Telz) was considering 

naming his son after his Shver Harav Avraham Yitzchok Bloch H.Y.D. 

He had a חקירה  Someone with two names is it 

1) one single name made up with two words in it.

2) two single names.

If 1) is correct then he can name his son " Avraham Yitzchok "

which is a completely different name than his own name " Yitzchok".

If 2) is correct then he can't name his son Avraham Yitzchok

which are two names and one of them is Yitzchok. 

(same as his)

R. Izak asked  Harav Eliezer Silver zt"l who answered him

that 1) is correct and a person with two names has a completely

different name than the person with one name.

His proof was from the Pasuk (Bamidbar 32:42) ונבח הלך וילכד -

Novach  named the city Novach after his   -ויקרא לה נבח בשמו

(own)name.

In the previous Pasuk when Yair b. Menashe named the villages

       because he had     בשמו  it doesn't say it was named     חות יאיר

one name, יאיר and called it two names(חות יאיר) 

that is not בשמו (his name)

As far as I know Harav Avraham Ausband shlita (R.Y. Riverdale)

is not named Avraham Yitzchok even though R. Eliezer Silver

Paskened that his father R.Yitzchok can name his son 

Avraham Yitzchok.

*There is a Bal Hatosfos named Yaakov Yisrael (Tosfos Chulin 112a dh Hani)