Wasnt it R’ Elyashiv Shlita who said he would prefer to earn Olam Habba on his own merits instead of relying on segulos? the story goes that he was asked to be sandek at a bris of a great-great (maybe just one great) grandson and he kept saying no. He was told, “its a segula of some sort to be the sandek at a great-great (one great?) grandsons bris”. He replied, the trip to bnei brak and the resulting recuperation necessary will take away hours from his learning. He would prefer to earn his olam habba by learning than “by segulos”. That is the story. I dont know how cedible it is, or isnt, although I heard it from someone who is pretty credible.
Then again, if you ARE going to learn torah and earn the brachos and havtachos mentioned in the torah, you may as well learn the torah of someone who promises something on top of that, get a double bracha. Maybe that is a dumb thing to say, didnt really think about it to much.