Dinosaur, I've kicked that - I had also kicked Mumsnet until DD started asking about bottoms and DW asked me to search here to find out what the Mumsnetically Correct term was for her you know what, and then I find myself posting on lemonstartree's thread. D'oh!
Routines are everything.
It's not true that blokes can't multitask, it just doesn't come natural. Yes I miss work (well not work, rather adult interaction) and days when DD or DS or both are ill (a lot recently) can mean no adult contact, Chris and Sue off CBeebies excepted, which is tough, but it's just the same as SAHMs have to face. The main difference is women can find it easier to break into toddler group cliques and school gate gangs - but if he already knows your friends from a/n classes and other SAH mums, then that's not always an issue. There is also some antagonism/head scratching from work mates/mates in general, but when they realise that he's getting amazing quality time with his children that they know they are missing with theirs and he can have the test matches on Sky Sports 1 on all day at the same time, it soon turns to envy. Hobbies in evenings and weekends out of the house with others - sports/band/pub - help with the feelings of isolation that sometimes rear their head.
Check out www.homedad.org.uk for a group of blokes in the same position, but tell him to keep checking MN for tips/ health issues / recipes.
So far as the mum is concerned, my DW, while missing the DCs, feels happy and confident that they are with someone who loves them as much as she does and who is prepared to put them before everything else.
Good on him (and you) BTW.