My understanding of considering credit is this: starting sometime on the morning of the second day, your effort begins gaining interest, regardless of who else the ercruit is considering. So, if you put in 100 "points" of effort the first cycle, then on, say, the 6th cycle it will be worth 103, and on the 7th 107, 8th 112, etc. This means, if no one else put any effort into this guy till the 20th cycle, your 100 points may by then be worth 180 or whatever. If someone put 70 points in at the same time you did yours, then you will slowly be pulling away from him, such that a 30 point lead in the first cycle may become, say, a 55 point lead by the 20th.
Make sense?