I can't remember any points at which Shirley Temple dances spontaneously
in her films. Although she does sing intense love songs to her
pseudo-daddy of choice (as in 'Dimples').
Although there are quite a number of discussions of Shirley Temple, none
that I've come across, analyze her dancing in terms of spontaneity.
However, James Snead discusses Temple's dancing in relation to Bill
Robinson (better than most of the discussions that focus on their sexual
tension) and black identity. Snead points out that her dances (with Bill
Robinson - which was about as 'spontaneous' as Temple numbers got) are not
so much performance as imitation. Well-written and sounds like it could
relate to your topic if you haven't already come across it.
Colin MacCabe and Cornel West edited "White Screens/Black Images:
Hollywood from the Dark Side" for James Snead (post-mortem) in 1994
published by Routledge.
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