A fair point, but:

• To the extent that humans are complicated enough to change unexpectedly on a moment to moment basis in that manner, the changes are not regular.
• To the extent that a human's decision theory or value change irregularly, any talk of optimization is moot, as irregularity necessarily leads to exploitable inconsistency at some level.
• Humans change their minds less often than they think.
• I rarely change my mind too, but estimate this frequency more accurately.