It is not quite true that any operation involving a null yields null. There are exceptions, in particular when a null literal (or something that is very close to a null literal) is involved.

Examples:

• null >> 2
• 2 >> null
• null & null (needs at least one operand that is not hard null)

Unusually this only applies to null literals; if you had a parameter/local that had a null value, the expression would evaluate to null as expected.