I reopen this ticket as we have many cases where fCellIncrementY has positive value.
We have cases reported by the following offices in different regions:
GISTEC, SHARJAH
ESRI KOREA INC, SEOUL
ESRI CANADA LIMITED, TORONTO
ESRI AUSTRALIA PTY LTD, BRISBANE
LOCUS LTD, DEVONSHIRE (Bermuda)
I'd suggest the following fix, which should be safer: