I too disagree with this concept. Someone once told me that a persons davening is strengthened if its said in Lashon Kodesh, but what she didn’t say was that when a person is really really davening from the heart with tears, the language wont make a difference. (At least thats my thinking).
Say for (just) a minute that ABC needs to daven 200 S”E before meeting her bashert, does that mean if she davens only 199 times, she wont ever get married? What about if she davens 199 times, and finishes sefer Tehillim 50 times, is that not counted? What if she davens 200 S”E and her bashert davens all that he needs, what happens to him? This whole thing sounds a little funny to me. And since she will never know exactly how many tefillos she needs, isn’t the point to daven?
I think maybe we’re getting a little caught up in certain things. I’m not c’v saying a person shouldn’t daven, but if a person works on themselves to be the best potential marriage material, and just davens and davens some more, (IMO) thats the best thing for a shidduch.