It would be extremely beneficial to be able to create 2 separate items on the same key with different "stored as"

Ive found many occasions (especially revolving around disk space). where I need to store both the "as is" value and the "simple/speed-per-change" delta.

For example
disk free rate - used to trigger based on rate of change
disk free - used to trigger based on absolute value

This doesnt seem to be currently possible through the GUI