Split, change focus and create new window with a single key combination

Hello everybody out there using screen,

A frequent task in GNU screen for me ist to split an existing window, focus the new area and create a new window within it.
This requires 3 key combinations:
C-a S
C-a TAB
C-a c
GNU screen is a great tool but why did the screen developers use such a uncomfortable way for this procedure?
Is there a way to get the intended behaviour with one single key combination?

Thanks in advance,
Julia