is it disparate impact when employer places conditions on intermittent leave to care for disabled

One of the circumstances is that the employer had placed conditions on the use of intermittent leave (FMLA/CFRA)that required employees to provide doctor notes to certify each and every time intermittent FMLA was exercised before the employee could return to work-even after doctor certification for intermittent FMLA had been established. There is no question that this is an FMLA violation as FMLA requires only one certification. My question is does such an employer intermittent leave policy in the abstract qualify as adverse impact since such a policy would be harsher on one group such as the permanantly disabled than others. For example, disabled parking takes into condiseration that without parking a close proximity to the entrace the disabled would be adversely effected. The disabled are set apart as a group with the severrity of the pain, mobility, and impairment-where even just walking a few feet can be extremly painful. Constant trips to thier doctor, at a time when they are in extreme pain, to certify each and every time home care is needed and provided before the employee providing care can return to work effects the permanantly disabled as group to an enormous extent. My question is does such an employer intermittent leave policy in the abstract qualify under adverse impact to a group like the permanantly disabled under title V11.