My VSO says using Voc Rehab risks hundo club / disability ratings in general. Is that true?

He said the logic being that if you are well enough to do Voc Rehab, the VA will think you are well enough to find a job, and will use this as an excuse to not use it. Im treading lightly on it, and have already used ample GI BIll benefits and dont think its worth risking......... I would be more skeptical if the other VSOs in the office didnt say the same thing. Are they giving bad advice or is this a real concern?