The larger effect blocks the smaller error. So, I use techniques that cover things well when I can. A good example of this is the demon face. You can see how we made a framework with 260's and then actually wove (not twisted) balloons into the framework. The untwisted balloons are stiffer and less likely to deflate since there's no stress on them. They also cover so much of the framework that imperfections can't be seen. Of course, even if a few visible balloons did deflate, you're eye isn't likely to catch them. This is true even on a basket of balloon flowers for a delivery. while they'll be able to take in the whole piece, no on eminds if a single bubble deflates. (To ensure that only a small section deflates, make sure to twist several times at each connection.)
Now, there are times that you have to do repairs. Usually if it's done well, the structure itself, will hold up. But, you may need to reinforce areas. I will take the time to twist in new balloons when that happens. Sometimes, just for aesthetics I will do the repairs also, but I pick and choose which things need attention and I always keep in mind that another balloon used in a different way can hide the imperfection. Hiding it is often easier than repairing it. It's like hanging a picture over a crack in your wall.