The old pseduobulbs do supply energy to the new growths of the plant. Sometimes, you will also find an eye at the base of the pseduobulb that can sometime become a new growth if needed. Can you remove some of them without hurting the plant? Sure. Just try to leave at least three or four healthy old p-bulbs with the new growth. When you repot this cattleya, place the new growth toward the center of the pot. This will allow it to continue to grow inside the pot and keep you from having it step out of the pot so quickly.
Here is an article to help too: Repoting a Cattleya Orchid, Step by Step