Quote from: lawabider on March 07, 2014, 12:07:28 AM

Quote from: Meni Rosenfeld on August 28, 2011, 12:04:16 PM

It doesn't help if N is chosen to be a given multiple of the difficulty at the time a block is found. If the difficulty is about to increase, it is more profitable to mine a short while before. For example, if N is set equal to the difficulty D, a share submitted D shares before the increase will be paid the full expectation in the D-window, and then when difficulty increased it will once again go inside the window and have more expected reward.

I am new to learning bitcoin mining, but I don't get your statement above: If N is set equal to D, then on average the window will just cover the round, so on average there will be no overlap.

That statement refers specifically to a change in difficulty at a roughly known future time. After the difficulty increases the retrospective window get larger, since it is a number of shares equal to the current difficulty.