'When the number of overt sumti exceeds the number of sumti places': see SE + x2-less brivla for the proposal that a nonce selbri-meaning is created that has a place structure that accommodates all overt sumti.
'When the number of sumti places exceeds the number of overt sumti': the current official rule is:
In usage, though, the rule is:
Xorxes has proposed (and I increasingly like the idea) that the rule should be:
Maybe I'll spell out the attractions of this when I have more time, but in the meantime I table it here for comment. --And
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