I mentioned above that I followed winter field beans, sown in October/November, with brassicas which is almost the same as brassicas following broad beans; tops are cleared to the compost heap and then brassica modules are planted within the left-in-the-ground roots. No need to kill off and no digging.
This sequence fits in very well with the no-dig system and I wonder if more experienced green manurers can suggest other sequences, particularly involving over-wintering green manures, which have worked for them.