(1) suggests that she said it once in the past.
(2) suggests that she says it repeatedly, or has said it on several occasions. This verb form is also used for the immediate past: she just said it a short time ago, and the speaker is still (unconsciously) viewing the event as part of 'now'.
(3) As with (2) above.
(4) As with (1) above.
The tense of the dependent clause it is an independent consideration. In (1 & 2) the moon continues to cause tides through eternity, irrespective of when she speaks of it. In (3 & 4) when he 'does it', a finite event, comes into play.