Resizing the spreadsheet
Basic commands:
C-o
M-o
C-k
M-k
w
TAB
Moves point to the next rightward cell, or inserts a new column if already at last cell on line, or inserts a new row if at endline (ses-forward-or-insert).
C-j
Linefeed inserts below the current row and moves to column A (ses-append-row-jump-first-column).
Resizing the spreadsheet (unless you’re just changing a column width) relocates all the cell-references in formulas so they still refer to the same cells. If a formula mentioned B1 and you insert a new first row, the formula will now mention B2.
If you delete a cell that a formula refers to, the cell-symbol is deleted from the formula, so (+ A1 B1 C1) after deleting the third column becomes (+ A1 B1). In case this is not what you wanted:
C-_
C-x u
Undo previous action ((undo)).