Laugs - I think that most HR people and lawyers in the field would totally agree with you that it would be a good thing to have more paternity leave rights for men. I totally agree that it should be up to the family to decide who takes childcare, when and in what proportion.
The thing that annoys HR people is this daft proposal that men can have the rights, but only if their wife/parter decides that she doesn't want them and goes back to work. To me, that still sends a very strong message that the primary right to leave belongs to the mother, and the father is just a back up option.
As you say, it would make life incredibly hard for HR people, but I'm also not sure that it would make life that much better for parents. If this really is about making parenting more equal, why is the right conditional upon the mother going back to work (which is where the minefield of trying to extract information from other employers, working out what on earth happens if the mother says she is returning and then doesn't, etc gets going)?
This is really my soap box if you get me going on it, but what I think would be far, far more helpful is if men could, for example, have the right to up to six months leave, to be taken in a single block (i.e not odd weeks/days) at some stage before their child is a year old (I take six months as an example. Ideally it would be parity, but I think you'd need to work up to that). There must surely be some way of adjusting through the benefits system so that, if the mother has gone back to work, the family does not lose out on maternity pay.
If you ran things that way, it would also have the potential to be more flexible if, for example, both parents worked part time. At the moment, you return to work and that's it for maternity pay, even if you're still in the payment period. How much better would it be if you could return, say, three days a week and keep 2/3 SMP until it ran out?
Fundamentally, it is a bodged proposal because the government isn't really committed to the cost and organisation required to sort this out properly. What they have come up with is impractical and open to all sorts of abuse and litigation. I think that, if they really meant it about flexibility, they'd do something a bit more holistic. The fact that they've gone quiet on the idea suggests to me that they weren't really sure either, and using Lord Mandelson to back away from the idea on the grounds of the economy smacks to me of them realising that it was an ill thought through plan.
Told you it was my soap box. It's not that I don't support better flexibility and rights, it's that I think that these don't go far enough and have the potential to really turn employers off the whole idea (because of the logistical nightmare), entrenching the idea that flexibility/leave is a 'problem'...