DynamicTextSpanner - 3 bugs?

[Fairchild]

The three score blocks below show three flaky things that don't seem to be
in the list.

In the first, the cresc. - - - - continues over the decr.

In the second, \setTextCresc and \setTextDecresc are reset after one use.
Bug or undocumented feature?

In the third, \override DynamicTextSpanner #'dash-period = #0 causes lily to
get lost and quit.

                           - Bruce

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\version "2.8.5" % Windows XP

{ \relative c'' {
\setTextCresc \setTextDecresc
c1\< ^"as expected, except line too long" c c\!\> c\!
\setTextCresc \setTextDecresc
c1\< c c\!\> c\! } }

{ \relative c'' {
\setTextCresc \setTextDecresc
c1\< ^"setTextCresc and setTextDecresc don't stick" c c\!\> c\!
c\< c c\!\> c\! } }

{ \relative c'' {
\setTextCresc \setTextDecresc
\override DynamicTextSpanner #'dash-period = #1
c1\<^"dash-period = 1" c c\!\> c\!
\setTextCresc \setTextDecresc
\override DynamicTextSpanner #'dash-period = #0
c1\<^"dash-period = 0" c c\!\> c\!
} }

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