I always string the soft string +3-5 lbs in soft string/poly hybrids. The luxilon string site recommended this and I have seen it recommended on other stringing sites by "experts". The idea is to compensate for the extra stiffness and lower resiliency of the poly.
Poly mains at 50 with multi cross at 53-55 is an example; poly will not stretch much and higher tension on multi brings it inline with poly resilency.
Gut mains at 55, with poly cross at 50-52 is another example. Stiff poly cross at lower tension plays comparable to soft main. Also, allows gut to slide and return.
I have been using this approach for 6 years for my rackets and my friends.
In same type string setup , I would drop cross tension 2 lbs or use same reference. Longer mains a bit tighter, lower crosses to allow mains to slide.
You are not doing it "wrong" with this hybrid approach.
Last edited by TennisCJC; 08-02-2012 at 06:39 AM.