It's a logical assumption, but a false one. You can easily test this, as I just did, with a lvl 30 character. I bought an attuned Siphon Insight (I actually bought a bunch just in case I proved myself wrong!). If your conjecture were true, then you would be able to convert it by type to a Cloud Senses, since the only level where they overlap is 30. I tried that and it failed, since the random generator didn't assign 30 as the level. If I kept it up, I presume that sooner or later I would get the luck of the draw and be able to convert, but a single false is enough to disprove your theory. So it basically is crazy!