Actually, think you could make the CF work using the simpler:
=OR($I1="A",$I1="T")
(just ensure that the active cell is on row1 in the CF range selection)

As for T, Excel's Help says:
If value is or refers to text, T(value) returns the value

Assume you have an "A" in I2

Without the T(...)
INDIRECT("I"&ROW()) will return it as an array: {"A"},
which isn't quite the same as "A"

With the T(...)
T(INDIRECT("I"&ROW())) =T({"A"}) ="A",
which returns the correct comparison as TRUE
ie T(INDIRECT("I"&ROW()))="A" is TRUE

--
Max
Singapore
http://savefile.com/projects/236895
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xdemechanik
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"Ken" wrote in message
...
Thanks, Max, that does indeed work! Thank you so much....I can start
eliminating all the extraneous rules....just one question: what is the
T function?? Just wanting to learn!
Ken