Beam severing

[Shane Brandes]

Working on the Godowsky challenge posed by Urs, I came up with this
really unpleasant workaround to splitting the beams as in the
original. Can anyone make this work without having to resort to adding
a second voice?

Shane

\version "2.18.0"

\relative c''

{<<{

\once \override Beam #'positions = #'(2 . 2) \tuplet 3/2{ cis,16
\sustainOn e c \set stemRightBeamCount = #1 g' \set stemLeftBeamCount
= #1 b, e }\tuplet 3/2{ ais,\sustainOn \set stemRightBeamCount = #1 g'
\set stemLeftBeamCount = #1 a, c gis e'}

}\\{\tuplet 3/2 {s4 \stemUp \once \override Beam #'positions = #'( 1.0
. 1.0 ) b8[ ais8] s4 }}>>}