1-All workers are stoped, a window with LP broadcast awaiting for the announcement that a block is found, the counter is reseted to 0 shares.
2-When a block is found i take note of the time to identify the first block later in pool stats, i start minig, automatically starts the counter...
3-For some hours i take note, for each block anounced in the LP broadcast, each begining an end time, amount of shares submited for each block.
4-Later after a few hours, i wait for a last block announcement, when it is announced i stop minig.
5-Wait for stats update, and when i see a none announcement in the statis begin to compare....
What is missed here?
That seems a bit overly complex and error-prone to me. LPs are sent for any blocks found on the network, not just those found by deepbit. Since a lot of the blocks are found by deepbit, your method may work well some of the time.
What you might want to do is log the exact time each share was committed, then add them up for the time intervals extracted from the stats page, obviously correcting for timezone as appropriate. (I'd suggest to both log in and set your deepbit preference to UTC, that way you can be sure you won't need to adjust anything.)
With this method, you may see a tiny amount of mismatched shares around the beginning/end of each round, but the share counts should match more or less.