true, but all missions you quote (apollo, probes, etc.) was ALL "single launches"

with a "single launch" you can wait months to have the right "launch window" to rendez-vous a comet, and, if the first launch windows can't be used due to a problem, you can wait and use the second (that may be six monts after the first) or the third, the fourth, etc.

with a "single launch" a mission (big apollo or little probe) NEVER can fails due to a "sum of delay", its only problem can be the "delay of the full mission"

the new moon missions will be the most complex ever made and the first that don't use the "single launch" architecture (like the apollo), also, the second launch will have a few "windows" in a few days; after 95 days the "windows" ends and the LSAM/EDS dies

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