My initial thinking is that InVi R: Touch, D: Dia, T: Taste, you are targetting the taste, but whom taste ? T: Ind is still missing, since it is replaced by T:Taste, how do you touch "Taste" of somebody else than yourself ?
I might be splitting hair, but it is strange, even inconsistent with the rule, that you can grant magical sense to one person without much effort, but requires an intricate MuMe with multiple requisits to grant it to a group of person.
From an effect point of view, MuMe, you are changing the mind of a target to get access to a new sensory input, InFo is this new sensory input. Why would it be possible to grant this magical sense to one person without MuMe but MuMe would be required for a group of person ?
When the mage is the only target, with R:Per, I can understand: the magic is feeding the mage the info he needs, and because he is a mage and he controls the spell, he does not need to transform his mind (MuMe not needed), but for anybody else the mind transformation is required.