diff --git a/lib/spack/spack/solver/concretize.lp b/lib/spack/spack/solver/concretize.lp
index fde2274cf97..70db459dd84 100644
--- a/lib/spack/spack/solver/concretize.lp
+++ b/lib/spack/spack/solver/concretize.lp
@@ -356,10 +356,6 @@ error(10, "Commit '{0}' must match package.py value '{1}' for '{2}@={3}'", Vsha,
      Vsha == Psha,
      VersionA != VersionB.
 
-% rule that says if a spec has a commit choose the max version that can accept a commit
-
-% rule that says if a constraint is on a commit and a version matches that commit then the constraint is on the version
-
 #defined version_satisfies/3.
 #defined deprecated_versions_not_allowed/0.
 #defined deprecated_version/2.
diff --git a/lib/spack/spack/test/concretization/core.py b/lib/spack/spack/test/concretization/core.py
index bab714a2f2d..9ea17522332 100644
--- a/lib/spack/spack/test/concretization/core.py
+++ b/lib/spack/spack/test/concretization/core.py
@@ -2735,11 +2735,6 @@ def test_phil_git_based_version_must_exist_to_use_ref(self):
             spack.concretize.concretize_one(f"gmake commit={'a' * 40}")
             assert "Cannot use commit variant with" in e.value.message
 
-    @pytest.mark.skip("not supporting on this branch")
-    def test_phil_commit_variant_in_absence_of_version_selects_max_infinity_version(self):
-        spec = spack.concretize.concretize_one(f"git-ref-package commit={'a' * 40}")
-        assert spec.satisfies("@develop")
-
 
 @pytest.fixture()
 def duplicates_test_repository():
@@ -3320,7 +3315,7 @@ def test_phil_spec_with_commit_interacts_with_lookup(
 @pytest.mark.parametrize("version_str", [f"git.{'a' * 40}=main", "git.2.1.5=main"])
 def test_phil_relationship_git_versions_and_commit_variant(version_str):
     """
-    Confirm that GitVersions auto assign and poopulate the commit variant correctly
+    Confirm that GitVersions auto assign and populates the commit variant correctly
     """
     # This should be a short lived test and can be deleted when we remove GitVersions
     spec = spack.spec.Spec(f"git-ref-package@{version_str}")
@@ -3331,6 +3326,46 @@ def test_phil_relationship_git_versions_and_commit_variant(version_str):
         assert "commit" not in spec.variants
 
 
+@pytest.mark.usefixtures("install_mockery", "do_not_check_runtimes_on_reuse")
+def test_phil_abstract_commit_spec_reuse():
+    commit = "abcd" * 10
+    spec_str_1 = f"git-ref-package@develop commit={commit}"
+    spec_str_2 = f"git-ref-package commit={commit}"
+    spec1 = spack.concretize.concretize_one(spack.spec.Spec(spec_str_1))
+    PackageInstaller([spec1.package], fake=True, explicit=True).install()
+
+    with spack.config.override("concretizer:reuse", True):
+        spec2 = spack.spec.Spec(spec_str_2)
+        spec2 = spack.concretize.concretize_one(spec2)
+        assert spec1.dag_hash() == spec2.dag_hash()
+
+
+@pytest.mark.usefixtures("install_mockery", "do_not_check_runtimes_on_reuse")
+@pytest.mark.parametrize(
+    "installed_commit, incoming_commit, reusable",
+    [("a" * 40, "b" * 40, False), (None, "b" * 40, False), ("a" * 40, None, True)],
+)
+def test_phil_commit_variant_can_be_reused(installed_commit, incoming_commit, reusable):
+    # install a non-default variant to test if reuse picks it
+    if installed_commit:
+        spec_str_1 = f"git-ref-package@develop commit={installed_commit} ~opt"
+    else:
+        spec_str_1 = "git-ref-package@develop ~opt"
+
+    if incoming_commit:
+        spec_str_2 = f"git-ref-package@develop commit={incoming_commit}"
+    else:
+        spec_str_2 = "git-ref-package@develop"
+
+    spec1 = spack.concretize.concretize_one(spack.spec.Spec(spec_str_1))
+    PackageInstaller([spec1.package], fake=True, explicit=True).install()
+
+    with spack.config.override("concretizer:reuse", True):
+        spec2 = spack.spec.Spec(spec_str_2)
+        spec2 = spack.concretize.concretize_one(spec2)
+        assert (spec1.dag_hash() == spec2.dag_hash()) == reusable
+
+
 def test_concretization_cache_roundtrip(use_concretization_cache, monkeypatch, mutable_config):
     """Tests whether we can write the results of a clingo solve to the cache
     and load the same spec request from the cache to produce identical specs"""
diff --git a/lib/spack/spack/test/packages.py b/lib/spack/spack/test/packages.py
index 7493747fa20..3fa9549a13d 100644
--- a/lib/spack/spack/test/packages.py
+++ b/lib/spack/spack/test/packages.py
@@ -349,7 +349,6 @@ def test_phil_package_condtional_variants_may_depend_on_commit(mock_packages, co
     assert conditional_variant.value
 
 
-@pytest.mark.skip("not supporting on this branch")
 def test_phil_commit_variant_finds_matches_for_commit_versions(mock_packages, config):
     """
     test conditional dependence on `when='commit=<sha>'`
@@ -357,4 +356,4 @@ def test_phil_commit_variant_finds_matches_for_commit_versions(mock_packages, co
     that commit is associated with the stable version of git-ref-package
     """
     spec = spack.concretize.concretize_one(Spec("git-ref-commit-dep+commit-selector"))
-    assert spec.satisfies("^git-ref-package@stable")
+    assert spec.satisfies(f"^git-ref-package commit={'c' * 40}")
diff --git a/var/spack/repos/builtin.mock/packages/git-ref-commit-dep/package.py b/var/spack/repos/builtin.mock/packages/git-ref-commit-dep/package.py
index 3f1122aa45d..a56131ad369 100644
--- a/var/spack/repos/builtin.mock/packages/git-ref-commit-dep/package.py
+++ b/var/spack/repos/builtin.mock/packages/git-ref-commit-dep/package.py
@@ -15,6 +15,7 @@ class GitRefCommitDep(AutotoolsPackage):
     url = git
 
     version("develop", branch="develop")
+    version("main", branch="main")
     version("1.0.0", sha256="a5d504c0d52e2e2721e7e7d86988dec2e290d723ced2307145dedd06aeb6fef2")
 
     variant("commit-selector", default=False, description="test grabbing a specific commit")