I have never had a problem with Glide but I have read of others who have. I did have a shredding issue with Superior Highlights poly thread and the sister product Rainbow (the variegated version of Highlights). But I believe this may have been a common problem because they seemed to discontinue the line. The only thing that solved the issue with Superior was very little tension on top and bobbin.
If none of the above suggestions work for you, it is possible you got a bad cone. Glide has always performed beautifully for me.