script opens Numbers document ok but then gives error -1728

Seems strange that this script will open Test.numbers but then fails on the get value statement with “Numbers got an error: Can’t get document …” number -1728 .

Is this the expected behaviour?

set theDoc to (path to desktop as string) & "Test.numbers"
tell application "Numbers"
	open theDoc
	tell table 1 of sheet 1 of document theDoc
		tell row 2
			get value of cell 1
		end tell --row
	end tell --table
end tell

Whoops!

If I had written

tell table 1 of sheet 1 of front document

instead of

tell table 1 of sheet 1 of document theDoc

the error would not have occurred.

Sorry for wasting time.