Never happen. The services always split the budget pretty much into thirds. Of course, the Army isn't shelving Future Combat Systems or Land Warrior to get tanks back into action, either.

One speculates that this may be an Army version of the old city hall trick: any time someone demands tax cuts, city council draws up a plan to downsize the police, fire fighters, ambulances, teachers and so forth. By showcasing how the current budget is inadequate to get our soldiers "the equipment they need" (more tanks?) perhaps some Army brass thinks that they'll get more cash out of the next budget supplemental.