No need to bother about erasing or not.
Long stuff read whenever you have time especially the links.
There is nothing either permanent or absolute or perfect to something as temporal or mortal as human life- as one among the many species- more so to individual human beings.
Everything is either intended or unintended manifestation in the process called evolution.
So what, if mistakes are made and remain without getting erased, it would be all the more helpful for others and posterity not to repeat similar mistakes.
Let the strides of evolutionary trends leave their imprints as they must, and there is nothing wrong, in fact in many cases they happen without our active participation.
Whenever I think of pen I think of the great things it can do on a blank page