Paladin spell affecting mount: SR check?

[TessarrianDM]

A paladin casts a spell while riding his special mount that affects other creatures {say, for example, Sacred Haven (SC 178), with a Target of "You and all allies in a 30-foot-radius burst"} in addition to himself. The spell has "Spell Resistance: Yes (harmless)". The mount has SR 21, and has not voluntarily lowered it ahead of time.

1. Does the spell (or can he choose to have it) automatically affect his mount, as per the Share Spells ability, without having to bypass the spell resistance?

2. If it does, will the effect end if they seperate by more than 5 feet?

3. If not, could he cast the spell, have it affect his mount via the Share Spells ability, and roll the spell penetration check to see if it can stay in effect if he chooses to dismount and they move away from each other?

 

[Shin Okada]

I read the rules as follows.

You casts the spell on yourself automatically, then tries to overcome your mount's SR as it is another target.

If you could not beat your mount's SR, you fail in casting the spell on your mount. Still, the mount is affected by the spell thanks to Share Spell ability. Then follows the usual rules for Share Spell ability rule.

If you could beat your mount's SR, the mount gets the effect of the spell because of 2 reasons. Having Share Spell ability and the spell is actually cast on it. In this case, the mount is actually affected by the spell in 2 ways. So, ending/dispelling etc. would be recorded separately.