On page 70 and 71:  Though in the code sample, you are using `sizeof(ThreadData)`: https://github.com/zodiacon/windowskernelprogrammingbook2e/blob/e23f9bb39c7dd6df8a408a6ace46e627211dcf5b/Chapter04/Booster/Booster.cpp#L91 As much as both are `8`, it could be misleading since the pointer size will stay the same regardless of struct change.