Most crucial elements in a light-weight C++ coding standard [closed]

Answer 1

Curly braces for any control statement. (Thanks to own experience and reinforced by reading Code Complete v2):

// bad example - what the writer wrote
if( i < 0 ) 
    printf( "%d\n", i );
    ++i; // this error is _very_ easy to overlook!  

// good example - what the writer meant
if( i < 0 ) {
    printf( "%d\n", i );
    ++i;
}