I think that for some chickens, broodiness is like a science that can't be tampered with (in the chicken's mind) So when two of mine went broody at the same time this spring, I left them in their chosen nests and left them to decide when to get off to eat and drink and socialize with their flock. Nobody tried to hurt their eggs while they were off.
One problem was that other hens would go in and lay their non-fertile eggs in with the fertile eggs we had bought (yes, even though there were FOUR other Empty nests available!) so I took pink nail polish and dabbed a mark on the fertiles. Every day I would have to count eggs and remove any unmarked extras.
The only way that I bothered the broodys was to candle. And I mean a LOT. To the point that my boyfriend would get nervous and think the chickens would no longer accept the eggs. They had no problem though and the hatch was fairly successful, 8 out of 12 possibles.