If using an unsealed polyester covering, such as Koverall, Supershrink Coverite, coat (clothes) lining material, the great thing about dope is that it not only seals the fabric, but will keep it tight for the life of the model and because most of it will evaporate, the remainder filling material (cellulose) is very light.
Nitrate dope can be used to seal and shrink, but not being fuel proof needs to be finished with butyrate colored dope or any type of paint.
The thing about nitrate is that it is very volatile, as in dangerous.
The same thing can be achieved by using butyrate from the start, believe you me, it works just as well, and it is fuel proof from the start.
If doing small models, use Sig's low shrink Butyrate, and you'll have no problem.
If dope is a problem because of smell, etc., you should not be using untreated polyester coverings.
I had a liking for Super Coverite, it already comes (if it is still produced) with glue on one side, so the need to apply dope to the bare surface was not needed, neither stixit or balsarite, and once the entire airframe was covered, a couple of coats of butyrate would seal the fabric and make it ready for painting.
This type of finish takes a little more time but it is by far the strongest and one of the best when it is all said and done, specially when doing scale models that used this same type of finish, although I have models of all metal big brothers, you can't tell what the finish under it is, as it looks just like a metal painted surface.
But dope smells and should not be used in confined and unventilated spaces, lots of vapors, they don't call it dope for nothing!!