What is a sMerit, something smaller than a Merit?
sMerit pretty much means sendable merits. This is so the Merit points you have under your name doesn't decrease when you give someone merits.
You have Merits, those you cannot send.
You also have sMerits, those you can only send, they have no other purpose.
When someone gives merit to you they lose sMerit of the amount transfered and you gain Merit as well as sMerit (which in case you can send again).
Eg should I send 10 Merit to you for a post, my sMerit would decrease by 10.
Your merit would increase by 10 and your sMerit would increase by 5.
Merits are exclusively earned, but the sMerit part you also get keeps the circulation flowing.
(Ignoring merit sources here, for the sake of making an easy example.)