The first Split($String,'%') (inside) creates an array:
'SMTP:kris.lutsock@ci.test.or.us','X400:c=US;a= ;p=MAC;o=MAC1;s=Lutsock;g=Kris;'

The second Split(Split($String,'%')[0],':') (outside creates a smaller array:
'SMTP','kris.lutsock@ci.test.or.us'
The [0] and [1] simply denote which elements in the arrays to use.
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