[quote=@Flamelord]
<Snipped quote by TwilightDragon>

Biggest problem I can see is that if the Servants are with their Masters when they're at school, they're all going to know the other servants are there (Besides Colt. But that's because he's a Modern Servant, so he can only pick up Mana if it's in large amounts as a result of Grail buff)
[/quote]

All servants should be able to sense each other once they are in vicinity of each other. And yes, a school gathering and stuff does sort of defeat the purpose of having servants and masters be concealed.