i had to make a repair in pvc with 2 slip couplings. if you have ever had to do this alone you know how hard it can be, since the glue wants to dry too fast before you can slide the slip coupling bcak over cut.
ever notice how if you glue a joint then pull it apart and try to re-glue the thing it takes forever for the glue to dry.
i used this to my advantage.
first apply primer then glue, then primer agian untill the glue is gone. the pve becomes like a sponge and stays good and wet. now apply glue agian and go for it.
obviously you can just get some slow-dry glue too...but in a jam this works.