You always have a problem when dealing with leased lands from the Federal Government or with grazing permits IMHO...particularly in today's environment.
Just look at what damage the Clinton administration did with the Wilderness Road Initiative and EO in the 90's when they unilaterally closed all of those forest roads that provided access to lands that had been legally leased for timber operations. Those companies (like Boise Cascade at the time) still leased the land, but now they culdn't access them and their leases and operations were worthless. Lots of money and jobs lost over that...which BTW we had hoped that Bush would summarily reverse through EO like it had been implemented. He disappointed us on that one.
If in fact there were leases that the Laney's cattle company had signed (irrespective of the fact that before the forest service ever came along they simply used the land) to which they had no clear title...and if in fact those leases expired upon due notification of the government who then had title/ownership to the land, then the Laney's have placed themselves, either through negligence or through a desire to confront the government, in a bad situation.
If that is the case, then this particular set of circumstances was just waiting to happen. I am very surprised it did not happen earlier and that is why I am still looking into this, figuring there is more to the story than my own understanding as explained above.
Now, this part about the grazing and the cattle and the government's attempt to recoup what it considers losses from the broken lease are irrespective of the Lanye's access to the 100 acres they actually own. I believe there are stautes on the books (federal ones and state ones) that allow an individual access to their own land across federal ground. That is a big issue in the case with the Pilgrim family up in Alaska.