Editing Straddling checkerboard (section)

===Setup===
A straddling checkerboard is set up something like this:
{| class="wikitable"
|-
! &nbsp; || 0 || 1 || 2 || 3 || 4
! 5 || 6 || 7 || 8 || 9
|-
! &nbsp; 
| E || T || &nbsp; || A || O
| N || &nbsp; || R || I || S
|-
! 2 
| B || C || D || F || G
| H || J || K || L || M
|-
! 6 
| P || Q || / || U || V
| W || X || Y || Z || .
|}

The header row is populated with the ten digits, 0-9.  They can be presented in order, as in the above table, or scrambled (based on a secret key value) for additional security.  The second row is typically set up with eight high-frequency letters (mnemonics for the English language include; 'ESTONIA-R', 'A SIN TO ER(R)', 'AT ONE SIR', 'AERO TINS'), leaving two blank spots; this row has no row coordinate in the first column.  The remaining two rows are labeled with one of the two digits that were not assigned a letter in the second row, and then filled out with the rest of the alphabet, plus the two symbols '.' and '/'.
* The period '.' is used as a full stop or [[decimal separator]],
* The slash '/' is used as a [[Escape character|numeric escape character]] (indicating that a numeral follows).

Similar to the ordering of the digits in the header row, the alphabet characters can be presented in order (as it is here), or scrambled based on a secret keyword/phrase.