This is how I grow rambling Bulbophyllums. I am pretty stubborn though, too - the pile of pins were used several months ago to turn the new growths back into the pot. I thought I had done a good job, but it just carried on and made new growths heading straight for the edge of the pot. One thing I forgot to do - is turn the new growths away from the light, sometimes they will change direction on their own. Bulbo Reverse Psychology - let them think it is their idea to stay in the pot.
I used to grow a similar species which had even longer rhizomes between each growth, Bulbophyllum masdevalliaceum. That was impossible, and I had to give in and find a new home for it. There is a short window of time to pin them down, before the new growths put out roots, but after the rhizome hardens up a little bit. You can wait, but this seems to be the best time to pin them down without snapping them off. Still, I always break at least one. This only seems to only encourage the plant to grow more. If I turn my back, I'm afraid I might find it rooted to the wall next time I look. Not sure who will ultimately win this battle, but smart money is on the plant. Maybe we could agree on a truce if I gave it a larger bowl, but that would be a sign of weakness.
Sarah Hurdel, NCOS member