When editing a formula and typing =sum... Excel offers suggestions for
typical items you might need. When =sum( comes up, I just hit tab, and that
prewritten function goes into the formula I am editing. It doesn't matter if
I'm in the middle of the formula, Excel just inserts it to the left of my
cursor between existing formula text. This also works for built in names.
If I have a defined name called Width, when I start to type =wid, Excel shows
the full Width as a choice and I can click tab to insert that name into the
function I am editing.

The new table functions don't work the same way. If I have a table column
with the heading Width, and start to type =[wid, Excel will prompt for the
full =[Width]. But if I click tab to choose this, Excel also deletes
everything to the right of the insertion, making this feature pretty much
useless. Is there any way to keep if from overwriting existing formula data?