To be honest, the fundamental problem I have with this episode (even though I did enjoy it on first watching) is that it seems utterly inconsistent with Spike being Twilight's assistant. Spike would not
be that useless at simple chores and still be helping Twi.
Plus, we've seen him doing chores before - not to mention helping Rarity! It's a fairly major plot hole that causes the whole story to fall apart, IMO.
Also, RD and 'Shy saved Spike's life in 'Secret of My Excess' - why didn't he serve them?
The character moments were great, and the animation was excellent, but the flaw with the central plot just overshadows all of that. It just barely holds onto a C.
"I'll wear this moustache..."