loom semantics around about push/stacking/clone unclear or buggy ?

There are test failures as of bzr.dev revno 3910:

ERROR: branch_implementations.test_push.TestPush.test_push_with_default_stacking_does_not_create_broken_branch(BzrBranchLoomFormat6)
    The branch 'file:///tmp/testbzr-i0FLk2.tmp/bzrlib.tests.branch_implementations.test_push.TestPush.test_push_with_default_stacking_does_not_create_broken_branch%28BzrBranchLoomFormat6%29/work/remote/'(bzr loom format 6 (based on bzr branch format 6)
) is not a stackable format. You will need to upgrade the branch to permit branch stacking.

ERROR: branch_implementations.test_push.TestPush.test_push_with_default_stacking_does_not_create_broken_branch(BzrBranchLoomFormat1)
    The branch 'file:///tmp/testbzr-i0FLk2.tmp/bzrlib.tests.branch_implementations.test_push.TestPush.test_push_with_default_stacking_does_not_create_broken_branch%28BzrBranchLoomFormat1%29/work/remote/'(Bazaar-NG Loom format 1) is not a stackable format. You will need to upgrade the branch to permit branch stacking.

ERROR: branch_implementations.test_stacking.TestStacking.test_stack_on_repository_branch(BzrBranchLoomFormat6)
    The branch 'file:///tmp/testbzr-i0FLk2.tmp/bzrlib.tests.branch_implementations.test_stacking.TestStacking.test_stack_on_repository_branch%28BzrBranchLoomFormat6%29/work/stacked/'(bzr loom format 6 (based on bzr branch format 6)
) is not a stackable format. You will need to upgrade the branch to permit branch stacking.

ERROR: branch_implementations.test_stacking.TestStacking.test_stack_on_repository_branch(BzrBranchLoomFormat1)
    The branch 'file:///tmp/testbzr-i0FLk2.tmp/bzrlib.tests.branch_implementations.test_stacking.TestStacking.test_stack_on_repository_branch%28BzrBranchLoomFormat1%29/work/stacked/'(Bazaar-NG Loom format 1) is not a stackable format. You will need to upgrade the branch to permit branch stacking.

The last two are fixed in bzr by:

http://bundlebuggy.aaronbentley.com/project/bzr/request/<m2vdtgb9pa.fsf%40free.fr>

They can all be fixed (with or without the above patch) by deleting branch.LoomSupport.clone.

As I understand it this may have consequences on an initial push (to the point where pushing a loom may requires a bzr init/bzr loomify first), thoughts ?

Are there some missing blackbox tests in the plugin ? None fails if clone is deleted...