First off, let me preface with that I do know that +1 and -1 counters cancel out.
Now, the cards for this play are:
To set the field, all are in play, and Arcbound worker has 2 +1/+1 counters on it. (Achieved when it was brought into play, triggering Hardened Scales)
The question is, if I give the Worker persist, have it swing, and try to bring it back from the grave, does it come back with a -1/-1 counter and a +1/+1 counter, and an additional +1/+1 counter thus resulting in a possible loop? Or do the counters cancel out before I can say Scales triggers?