@Background Pony Number 17  
Yeah. You’re right. After Capper sent the Mane Six and Spike to Mount Aris, he tricked Tempest and Grubber that they’re heading east to Black Skull Island instead of going south to Mount Aris and/or Seaquestria. And later on in the film, Tempest sworn revenge on Capper for tricking them and not telling them the truth. I don’t know why Capper doesn’t want Twilight to get caught by the Storm King’s army because he tried to fool Tempest and Grubber for showing them that they headed east to Black Skull Island rather than heading south to Mount Aris and/or Seaquestria. That wasn’t until Rainbow Dash’s sonic rainboom goes off and Tempesst gets revenge on Capper for tricking her and Grubber.

…you live…in a windmill…

Maybe? That’s no maybe. That’s some genuine guilt.
 
@Background Pony Number 17  
@Amethyst_Crystal  
Exactly. It’s kinda sad that he didn’t really expect kindness from others.

@Background Pony Number 17  
Yeah. I think some fans over-emphasize on what she did,  
just sewing a sleeve and adding two buttons to a jacket,  
which for her is not much at all (but she lacked supplies and time).
 
And even though cats care a lot about appearances,  
it’s nice to think even a jaded criminal like him,  
could be moved by a real ‘thank you’ like that.

He was. Rarity’s generosity is what spurred him to lie to Tempest Shadow about the ponies’ whereabouts.

George Harrison would be a better boyfriend for Rarity.