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As far as I know, no. The heals wont stack on one individual. It should be that each consecutive use will overwrite the last heal, if that's actually how it works I couldn't say.
I do know that when using it multiple times, one person wont get multiple ticks of the effect.
If there are more people around, it will spread them around to the people instead, similar to how Rapid Regen/Mutagen works from the resto staff tree.