We both work fulltime.
I leave before him so although I set up breakfast, he deals with it and the cleanup, as I have to be out for my 2 buses to work by 7.15am
He also gets home earlier than me 3 nights a week.
So...
Monday - Friday mornings - he has an hour with them more than me
Monday - Wednesday he has them for 1.5hrs more than with me
We share stuff on the weekends, although he does take them swimming - but then if we're visiting GPs I tend to do that on my own with them anyway... it probably evens out too there.
But overall he probably does spend more time with them alone than me, actually, now I think about it. Not by much though.
It's much easier if you have a similar work commitment outside the house, because it's much more transparent about what balances there are..
I know that when he was PT we did have a few discussions about this very thing... and when I was on ML a few years before I felt as though he'd started to (whether conciously or not) designate everything to do with the household to me. That was hard - and it took a firm effort on my part to put a stop to it. I think having a husband who, when faced with the facts, knows he shouldn't be taking the piss, helps.
Put it this way: DH and I always agreed on the split between work and work in the home/childcare. When it started to slip on a practical day to day level I made a little diary to prove to DH how much he was taking the piss during ML. But it did take that proof!