I like your idea. They do close weekends, some on holidays, and don't have a full answer why, but cancer repopulation, angiogenesis, hypoxia may factor in, and tumor cells are different than regular cells, and sure studies were done finding this was the most effective way for tumor kill, so far, in most cases, since regular cells have a certain cell cycle, and death, but cancer cells don't, and that factors in probably too.There are other ways to deliver radiation that can increase boost dosage, more fraction sizes, hyperfractioned radiation, which is more than once a day, accelerated fractions for shorter duration over the course of the treatment with same dosage, so that may factor in for any planned lapses, type of treatment. Certain organs, structure, like skin, can recover in less than a day, and each has a maximum dosage level before unacceptable toxicities begin, so that is factored in. In some SCCHN they use split dosages (hyerfractions) 2x a day treatments, and even 6 day fractions in 6 weeks (accelerated fractions) instead of standard 7 or adding on a day towards the end of treatment to increase total Gy. There is brachytherapy that uses one time high dose or several weeks, or longer implant doses. I had HD-IORT..high dose Intraoperative radiation therapy, in addition to IMRT. IORT is done during surgery directly to the exposed tumor, which gives a one shot high dose of radiation from 10-25 Gy, which would take two to four weeks with IMRT.. Radiostatic Radiosurgery uses high dose in less time also, like in 5 treatments. They are working on radiation to be more effective with medications, even with Chemo, administered during radiation to make tumors more radiosensitive, less hypoxic, and others.