In this instance, Pilot says that it’s the heat generated through friction between the pen’s “eraser” and the paper which rubs out the ink. And it actually does work. Take a look at the two pictures below – the top one shows the writing, the bottom one shows where I’ve rubbed out the ink.
Ok, so you can see a faint trace but in practice, if you re-wrote over the (erased) writing, you’d never know. You’ll also see that the paper is undamaged. The “eraser” on the end is a rubberised nub that doesn’t seem to wear out or leave bits of rubber behind.
So if you are looking for an erasable pen, pick up one from your nearest good stationery retailer. Available in 8 colours and also in a stylish executive version.