Is the CBA helping or hurting students?

I recently talked to a group of teachers about their views of the current SPS teachers CBA and its impacts on SPED students. I was expecting the group to do the usual evangelizing how the union has pushed for progressive changes that benefit students. You know like smaller class sizes ect.

Instead of glorifying the CBA I heard this:

"I think the CBA hurts SPED students by confusing what rules I should follow, the CBA or SPEDs."

"My contract dictates my responsibility to my students, if its not in the contract I usually hesitate to do it"

"The CBA prevents me from doing what I think would be best for special education students"    

I then asked what should the new CBA include for SPED? I only got one responce.

"The new CBA will need to have language to protect us from special ed students effecting our ratings, because if my performance is going to be rated on test scores why would I want SPED students in my class. My chances for a good rating will be low."

It seems to me if all teachers are going to be rated on students test scores then they will focus on bringing up the performance of the lowest performing students SPED or not. This will naturally benefit all students because teachers will push for curriculum that works for all and class sizes that work for all, but only work if the teachers are rated on each individual students academic performance not the class average.

 I would further argue a good teacher could with the right tools make the largest gains with the least performing students. We could see teachers fighting over special education students instead of dreading them being assigned to their class rooms then ignoring their struggles.