Hey Carl !
I see nothing wrong with your method of repair. If the glass comes loose from the base there is nothing wrong with carefully attaching the two back together again.
There is one issue though that I think deserves consideration. If the repaired lamp is later sold, especially if it is of any considerable value, then I feel that it is the responsibility of the seller to disclose the fact that repairs were made. Consider the fact that once the glass and base become seperated, the original condition of the bulb has then been altered and, even though repairs have been made, the original bond is no longer intact. That's my opinion.....Ha Ha Ha.....whatever it's worth.