I imagine that letting them under absorb under your tounge would be ideal, because what is absorbed doesnt get lost through digestion. Also, anything that doesnt get dissolved or absorbed is simply swallowed. If i have time i always let mine disolve under my tounge. I thought that it just melted, but I swear that now i know that at least some of it is being absorbed.
I belive this is why many people find papervar to be more effective. Someone posted that the papervar is only absorbable because it has some special chemicals. I think that this is bullshit, and I havent seen any evidence to prove it.
Let them dissolve, It cant hurt, but can only help.