Conrad Carlberg wrote...
Hi Harlan,

I still don't have a "crisp" definition (g), although I haven't before seen
a listing such as you provide. I doubt that a crisp definition exists.

I would quibble with

LINEST, LOGEST and FREQUENCY, don't require array entry per se.

Formally and syntactically, that's true, but as a practical matter array
entry is required -- how many times have we seen users in the ngs frustrated
because they couldn't seem to get the full results promised by the
documentation? As you subsequently point out,
....

Failure to read the full documentation on array formulas is whose
fault? Microsoft's, which includes the following text in online help
for MMULT:

"Note The formula in the example must be entered as an array formula.
After copying the example to a blank worksheet, select the range A8:B9
starting with the formula cell. Press F2, and then press
CTRL+SHIFT+ENTER. If the formula is not entered as an array formula,
the single result is 2."

Or, just perhaps, the users?

As they say in other newsgroups, RTM, and when that doesn't work, RTFM.

The need for array entry *should* be obvious when an array result is
expected.

Finally, there are contexts when LINEST or LOGEST could be used in
formulas to produce scalar results. If those formulas only require
SUMPRODUCT or similar functions, then the entire formula may not
require array entry.