diff --git a/cockroachdb/src/jepsen/cockroach/client.clj b/cockroachdb/src/jepsen/cockroach/client.clj
index 9190e7fbb..fbb2396b6 100644
--- a/cockroachdb/src/jepsen/cockroach/client.clj
+++ b/cockroachdb/src/jepsen/cockroach/client.clj
@@ -116,6 +116,17 @@
     (assoc op :type :fail)
     op))
 
+(defn with-idempotent-txn
+  "Takes a predicate on operation functions, and a txn op, presumably resulting
+  from a client call. If idempotent? is truthy for all of the txn's operations,
+  remaps :info types to :fail."
+  [idempotent? op]
+  (let [[_ txn] (:value op)
+        fs      (map first txn)]
+    (if (and (every? idempotent? fs) (= :info (:type op)))
+      (assoc op :type :fail)
+      op)))
+
 (defmacro with-timeout
   "Like util/timeout, but throws (RuntimeException. \"timeout\") for timeouts.
   Throwing means that when we time out inside a with-conn, the connection state
diff --git a/cockroachdb/src/jepsen/cockroach/multiregister.clj b/cockroachdb/src/jepsen/cockroach/multiregister.clj
index b65b86d6f..e94d1cd35 100644
--- a/cockroachdb/src/jepsen/cockroach/multiregister.clj
+++ b/cockroachdb/src/jepsen/cockroach/multiregister.clj
@@ -64,7 +64,7 @@
             (info "Created table" t))))))
 
   (invoke! [this test op]
-    (c/with-idempotent #{:read}
+    (c/with-idempotent-txn #{:read}
       (c/with-exception->op op
         (c/with-conn [c conn]
           (c/with-timeout
@@ -73,7 +73,7 @@
                 (let [[ik txn] (:value op)
                       txn' (mapv
                             (fn [[f id val]]
-                              (let [t (id->table id)
+                              (let [t    (id->table id)
                                     val' (case f
                                            :read
                                            (-> c
@@ -115,7 +115,7 @@
                             (fn [k]
                               (->> (gen/mix [r w])
                                    (gen/stagger 1/100)
-                                   (gen/limit 100))))}
+                                   (gen/limit 60))))}
      :model       (model/multi-register {})
      :checker     (checker/compose
                    {:perf   (checker/perf)