You've forgotten what a measurement is. A measurement is any interaction between particles. In the case of entangled photons, a measurement consists of allowin

You've forgotten what a measurement is. A measurement is any interaction between particles. In the case of entangled photons, a measurement consists of allowing the photon to be absorbed by an atom. You only get one such measurement; any new photon emitted by that atom will have a spin which is no longer entangled with the spin of it's original twin. (Actually, they were more like anti-twins; one was up when the other was down, and visa-versa.) Even assuming you had two larger particles (let's say atoms) which were entangled, allowing you to make multiple measurements, nothing you change about one of them is communicated back to the other. If you measure a property of your atom you may also be able to determine the value of that property for the other, but in doing so you change the atom. You flip the spins of the electrons, or of the atom as a whole, etc. This is what "clearing your measurement" means; you no longer have any good information about that property. If you then remeasure that property, it's value is no longer correlated with the twin particle.