Anytime you increase plant size, be it leaf or flower, it will not only store water, but will require more water as the respiration surface area and need increases.

Also, different nutes are also required by the flowers and the additional nutes require more water for transport.

Though, that would be a strange way to say it, with yellow spots. I don;t think they're related....

Maybe just an oddity of the plant.

If its on flower and its the only leaf like it I would remove it.