Q.
Is it necessary to do the whole process of filing with water and changing 3 times the water, isn't there a shortcut?
A. You may place the glasses on a boiling pot as normal kashering is done. We follow the process of Miluy Veiruy described to avoid cracking the crystal. You may place the glasses on a pot prior to heating and boiling, thus avoiding this problem. You have to take the utensils to a Mikve and immerse them without a brocho, if you are in doubt if it was done by the previous owner.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit"a