This. At least to a large degree. I once had a Pure Mortal PC who specialized in weaponized Catches (he had Occultist with a focus on it, even) and we talked about how you weaponize true love and determined there was basically no way to do it. I mean, I suppose you can theoretically trick them into feeding on someone in love...but that's way more awkward and difficult to arrange than it's worth most of the time, and isn't actually likely to damage them that badly unless you have them tied down or something (and any Catch you have to tie someone down to use is pretty close to useless). None of this would technically reduce the Catch by the rules, I admit, but it's enough to justify the lower price to me, at least.
I have a slightly different take on catches. Sometimes the bonus you get for how obscure the knowledge is isn't completely based on the catch itself.
I'll use the True Love or Silk (I just recently used Silk in another thread, because I have a character who has a catch of "flowing silk")
Maybe finding the knowledge that "true love" is their catch is a +1, but finding out the only way to weaponize it is to find a wedding rings from a couple that has been married for 50 years and forge them into the hilt of a sword, would make it closer to +0.
In the Silk example, my GM and I decided that getting silk was pretty common +2, finding out the catch would be around +2 because people could wrap it around clubs and fists and stuff, in a pinch, we decided to put it to +1 and make the method of using the Catch more of a mystery...so to use it on a sword or any weapon effectively, the silk had to be attached to the hilt(for the sword) in advance while saying a small prayer. So while the silk, itself, wasn't going to be hitting my character, the presense of the silk and its association with the sword allowed the sword to act as a catch.
So the research isn't only WHAT the catch is but HOW to use the catch effectively.