Hmmm, funny: I've been on Red Javas (tenor, 2.5, 3, and 3.5) for years and never did anything to them; 3 out of 5 would play right away, the other 2 after a short breaking-in period. Since about March, I've experienced major issues, so I finally bought a Reed Geek this fall, learned how to use it properly, and that has indeed made a difference -- still, I consider myself lucky to get 1 gig-worthy reed out of 2 boxes after working on them diligently. The rest of 'em are good enough to practice on, but... The Red Javas for alto have been even worse for me, even though I don't play alto much. One day in the summer I went through a box of 10 and actually thought my alto needed to go the tech for sudden mystery leaks before, in desperation, I slapped on a different brand reed (an old La Voz I think it was) and realized it was those dang Vandorens. It got so bad that I invested a whoooole lot of $$$ in synthetic reeds, yet didn't find anything I liked. So for now it's back to the Reed Geek and the Vandorens, hoping, hoping, hoping that it was just a bad harvest or something...? I still have a stack of Vandoren Reds left, but I'm thinking about switching reed brands, I just don't know to what.........I played Blue Box for a good long while trying to get them to work.
I experienced the exact same thing. Even in the right strength the way they are cut makes it seem like you are blowing into them rather than past them. A little bit of work and breaking in and it gets better but then they start to close up.
My solution was an easy one. I switched to red Javas. Still dark but way more free blowing.