The shock waves from the earthquake are conducted through the earth's crust, mantle and core like an echo.
The variances in the Earth's structure like different forms of rock, tectonic plate interfaces, molten core, sea water all affect the transmission of the shock waves and they scatter and bounce around. The waves, their "echoes", the reflected waves all interfere with each other for quite some time (some reinforce each other, some counteract) until they dampen.
Some of that energy is manifested in a direction counter to the Earth's rotation. That impact is so small it can't be measured by the tactile senses but it can be measures with precision measuring equipment.
I understand that. What I'm curious about is whether it slowed us, stopped us, moved us forward or what. All I've found was that blanket statement with no data or application of that data presented. The one statement that the rotation has been affected is such a general pronouncement that more details are needed to properly interpret it.