GridCells property strange behaviour

I have a TDBAdvGrid called myGrid. Let's say that cell (1,2) holds the string 'Test'

When I perform
myGrd.GridCells [1,2]
I get an empty string returned.
When I call myGrid.Cells [1,2] I get the string 'Test' returned.
When I debug into the code I see that all GridCell does is to relay the call GridCell to the Cell function.
Can anybody explain this strange behaviour?
TIA and regards