The 1895 Fort Bleknap agreement was negotiated by the U.S Government under the same directives and guidelines that was negotiated with the Blackfeet the same year it appears to me. One of the claims by the tribes on the Fort Belknap is that they were threatened with starvation if they didn't sign over the lands. An examination of the record does not show that this was true. The 1887 treaties with both the Blackfeet and the tribes on the Fort Belknap Reservations contained language for subsistence support for a period of years. It was recognized by the tribes and the Indian Department in 1895 that this subsistence support would run out and have to be renegotiated because the tribes were not making fast enough progress in becoming self sufficient. In both the Blackfeet agreement and the Fort Belknap. there is an extension of this subsistence support. One will also notice that the sum of money paid per acre in the Fort Belknap agreement is a lot more that what land was going for at that time. Justification for that is explained the agreement because the federal government recognized the mineral value of the land.
One has to realize upon reading the two agreements that there was tremendous pressure on the government to solve severe trespass issues by miners into both the Rocky Mountain Front and Little Rockies on the perspective reservations. Gold had a been discovered in the Little Rockies. There was no way the government was going to keep the miners out of these lands short of using federal troops which wasn't a popular option from the governments perspective. I'm not sure it would have been from the tribes either as the army was not well thought of by the Indians at that time. It would not seem that the general public would have supported it either. In my opinion the record shows that in both cases of the Blackfeet and Fort Belknap agreements, all parties did the best they could and did not try and screw the other side. Non-the-less, 125 years later it is quite popular to say by some that the tribes were pressured with starvation if they did not sign over the lands and that the government did not pay enough. They use this argument to justify transferring federal and state lands to tribal control in the proposed Fort Belknap Water Compact Bill. This seems unrelated to water rights issues the tribes, state and federal governments are working out but apparently not. I'm not close enough to the negotiations to know why the two issues are in the same Water Compact Bill. Giving back the National Bison Range is now included in the proposed Salish Kootenia Water Compact Bill too so this isn't the only place it shows up.
Tester's proposed bill has 27,709 acres of of state lands that would be transferred to the Fort Belknap tribes control of which 7,413 acres are off the reservation. I'm not sure what the justification for the off reservation state land transfer is but all of the 27,709 acres value would have to be made up to the state by transferring an equivalent value of federal lands to the state. The proposed bill states that these federal lands would have to be within 100 miles of the reservation and would have to be transferred within 15 years of passage of the bill. I would assume BLM lands would be used for this. I'm also assuming that all the state lands are school trust lands which primary purpose is to make money for the schools in Montana. While transferring the state lands on the reservation would not be an issue from a hunting perspective, transferring the federal lands to make the state school trust whole is. School Trust lands have one purpose and that is to make money for the schools. That is why we are charged a fee to recreate on it. School Trust Lands do not have all the protections and public involvement requirements that federal lands do. The state could at some point decide to sell them which has been proposed in past legislatures. This is why Senator Tester and some of the groups supporting this bill have stated at public land rallies that states should not be trusted to manage all our federal lands if they are transferred. Yet, that is exactly what they are proposing here. They are also supporting the public losing all of their rights on the federal land given the tribes when it comes to how those lands are managed. No public input on managing these lands and the state could sell theirs if it could get through the legislature and a governor. We have been lucky in the past defeating these proposals but it only takes one legislature and a governor that thinks it is a good idea and that is the end of it. I would much prefer it stay in federal ownership as public land than transferred to the state or the tribes.
I should point out that the land transferred to tribal control would still be held in trust by the federal government, so it could not be sold. There is access provisions for the tribally controlled land too as you have noted but it would not be the same as it is now under BLM control. Any conflicts would have to be resolved in tribal court.
In regard to the state lands given the tribes, it would seem that it would be better for the federal government to put money in the state land fund that is used to buy private lands to block up state lands. Several legislatures ago, a bill was passed which allowed the state to sell isolated lands. That money was put in a fund that would be used to buy blocks of private land from willing sellers. This fund was used to buy a large farm on the Yellowstone I believe in the last year or so. It also allows the state to buy more productive land in blocks which brings more money into the school trust. It also provides better access for the recreating public which is primarily hunters By doing this, our federal lands would stay intact and would not become a politicians piggy bank as is the case in Tester's proposed bill. It would give the state more flexibility on what type of land they acquired. Since the proposed Water Compact bill has over $600 million for water development, it would seem that Uncle Sam financing the state land purchase fund for the value of the almost 28,000 acres the state transfers to the tribes would not be unreasonable.