Elsewhere, the changes are head-snappingly fast.
What does 'head-snappingly' mean?
Is it an informal word?
If you turn your head very fast eg to look at something that has gone past you very quickly, we can say that you snapped your head around. The writer knows this, and has decided to invent a casual adjective. The changes are head-snappingly fast means they are very, very fast.
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If you turn your head very fast eg to look at something that has gone past you very quickly, we can say that you snapped your head around.
The writer knows this, and has decided to invent a casual adjective.
The changes are head-snappingly fast means they are very, very fast.
Clive