There is no need for part 91 reposition flights and the FAA has already said that it is a violation to bounce attenpt to circumvent between the two with the sole intent of avoiding the 14 hour rule.
Another statement used way OUT OF CONTEXT!
They have also stated that they are not concerned with Part 91 operations when medical crewmembers and patient are off the aircraft! Matter of fact, it is stated so right in the FINAL RULE publised by the FAA when they adopted Subpart L:
The FAA did not propose any substantive changes to §§ 135.267 and 135.271 flight time and rest requirements but instead added language to those sections to clarify “flight time” as a term that includes any helicopter air ambulance operation as defined in § 135.601. As established by this rule, all helicopter air ambulance operations with medical personnel or patients on board must be conducted under part 135. The provisions of §§ 135.267 and 135.271 would therefore apply to the helicopter air ambulance operations previously conducted under part 91.
Additionally, the FAA is not changing the rule language to provide a more extensive list of flights that must be conducted under part 135. As discussed above, the rule is clear that if medical personnel or a patient are on board the aircraft and the flight is conducted for medical transportation, then it must be conducted under part 135. The non-exclusive list is intended to emphasize that the traditional three-legged helicopter air ambulance flight (base to pick-up site, pick-up site to drop-off site, drop-off site to base) must now be conducted under part 135.
1. APPLICABILITY OF PART 135 RULES TO HELICOPTER AIR AMBULANCE OPERATIONS (§§ 135.1, 135.267, 135.271, 135.601)
The FAA proposed requiring that all helicopter air ambulance operations with medical personnel on board be conducted under part 135 operating rules. Flights to pick up a patient, the patient transport leg, and the flight returning to base after the patient is dropped off, or other flights with a patient or medical personnel on board would be conducted under part 135. The FAA received many comments from organizations and individuals supporting and opposing this proposal. Comments addressed the FAA's accident analysis which formed the basis of the regulatory evaluation; whether part 135 is the appropriate part of the regulations for this change and whether repositioning flights should continue to be operated under part 91; potential limitations on operations; flight and duty questions; and how the FAA defined flights to be conducted under part 135. These comments are addressed in detail below.
DEFINITION OF MEDICAL PERSONNEL
The NPRM defined “medical personnel” as “persons with medical training, including, but not limited to a flight physician, a flight nurse, or a flight paramedic, who are carried aboard a helicopter during helicopter air ambulance operations in order to provide medical care.” With this rule, any flights for medical transportation that carry a patient or medical personnel must now be conducted under part 135 rules.
Additionally, the FAA acknowledges that certificate holders may not be able to conduct certain operations because of the more stringent part 135 requirements. For example, the weather minimums may be below part 135 standards, but would have been acceptable for a part 91 operation. Similarly, additional part 135 flights may mean that a flightcrew member reaches flight time limitations more quickly. Nevertheless, the FAA has determined that these restrictions are appropriate given the increased safety of operations that are expected as a result of this regulation. However, the FAA is not extending this regulation to flights conducted without medical personnel onboard. The FAA has determined that such an extension would go beyond the stated rationale of providing additional protections to the medical personnel and passengers onboard the helicopter. [Emphasis added]