I am not sure how this works. Lets say we have path of 4 for a transaction. A - B - C - D Lets say 100usd transaction amount. For the sake of arguement, lets

I am not sure how this works. Lets say we have path of 4 for a transaction. A - B - C - D Lets say 100usd transaction amount. For the sake of arguement, lets consider every node has 100usd credit one way (reverse path) So if A want to send 100usd to D. A gets 100usd credit from B, B gets from C and C gets from D. Until D spends money, system is locking 300usd credit for 100 usd transaction?