Tent fabric should not be blistering or peeling before you attempted to rescue it.
This is quite common when Tents have been stored for long periods, and very prevalent if the Tent was stored not fully dry, or in a damp environment or also if stored in a high-temperature location. Probably 90% of “Nylon” tents today are made of Polyester of varying grades from different Countries and Textile Mills, generally coated on the inside with Polyurethane for water resistance and often times the outside with a polymer for UV resistance. Some superior models also have a Flame-retardant coating. These coatings also give the base-fabric additional strength. With water-ingress from damp conditions or layer-melt from high heat during storage, the coatings will either lift away from the base Polyester or the layers will bond together and tear when the Tent is opened.
If the fabric is then washed or brushed to remove the flaky bits, the coatings are destroyed and the fibres of the Polyester also damaged.
No Waterproofing liquid Sealer is going to give the perished fabric a new life. In some cases, on small (about 3cm2) brushed areas, the Sealer will bind the fibres back together quite effectively and the Tent will last another year or two, but larger patches will likely still allow water through, even after many brushed-on coats of Sealer. The “foundation” to build on, is just too fragile.
I want to assure that we have been selling DripLock very successfully for over 10 years. If the product “does not work” we certainly would not even be offering it. Our reputation is too valuable to us to risk.
Incidentally, the formulation used in Drip-Lock is identical to other Brands such as NuSeal, CampGard, NuProof, Rainblock and several others on the market and produced by one factory.