Thanks to everyone who replied. Not that many times, by the way, can you use a bag/balloon for the same hit. Which is fine anyway, because there's fresh stuff burning in your other hand.

Also, I should say I don't ever claim to actually know something or anything, about anything, but even then no one can say there is as much "officially" known about marijuana as there is about tobacco or alcohol, and since the only result of everybody always arguing (not that I'm saying anyone here is arguing) over whether or not holding hits in is effective is just more arguing, I prefer to go by what I feel rather than by what is supposed to be common knowledge. In any case, with weed being such a persecuted thing as it is, it's not uncommon for incorrect information or generally kind of chaotic, vague information to be purposefully spread about it. Not that everything I disagree with is incorrect, but the less people can find to agree on verbally between each other, the more confusion and chaos there is going to be surrounding discussions about something.

Anyway, I have since used both the bag and a balloon, and for probably generally the same reason that a high is a little different if the surrounding smoke continues to be inhaled and exhaled until its dissolution, this technique of recycling any smoke to whatever potential it has left works. There are some things about the air-tightness and the quality of the bag, and the exact process that takes place when using a balloon, that I don't understand yet. I may or may not continue to try to find a better device for the technique, but just breath itself can be used, too.