nink wrote:
Regardless of the situation, one should never burn any bridge. Even though your ex boss won't be much of help right now, you have to think long-term - not just short term. Most bad decisions are made when one considers only short term consequences and results. Therefore, you are RIGHT to find an alternative way to notify him that his service is no longer needed.
If you can find a replacement recommender, then go ahead and delete your recommender's email or contact info from the online application and add the new recommender. Then politely email your ex boss and let him know that due to approaching deadlines, you acquired additional rec letters from other sources and thank him/her for his time and interest. Let him know that you might need additional rec letters to these schools in the future (in case you are WL'ed etc) and you hope he/she will assist you in the future.
I think nink has it right. Don't burn any bridges, but don't rely on him either -- this is too important to you.
I think in general, you want to secure recommenders who would be "disgusted" if you didn't get into your top choice schools; someone who is
really rooting for you. This isn't exactly the same as the person who you worked with the most closely, had the best project experiences with, etc. If those people are either stingy with their recommendations or dodgy, best avoid them. People have
weird pre-occupations with schooling, favors, etc.