1. Is it really as simple as this ?

In theory, yes. However, to get the full Tesco benefit takes a lot of effort. Look at the Tesco thread(s) for full info.

2. Does anyone have any additional/better suggestions ?

Note that you will only be able to get as far as Australia on the 2-4-1, as it can only be used on BA flights. To get to NZ, you'll have to book a seperate flight from Oz.

If you're willing to go with Emirates and are willing spend dosh, they tend to be cheaper (but offer a good service), and they do an AMEX 2-4-1 on paid fully flexible fares. You have to book via the AMEX Travel Service.

3. How long does it take for the Amex 2-for-1 voucher to be sent after we reach £10,000 expenditure ? Is it sent after we reach £10,000 or after a year ("if you've spent £10,000 on your Card in one year")?

About a week.

4. The BA website (http://www.britishairways.com/travel...r/public/en_gb) says “You will be able to book standard redemption tickets up to 3 days before departure where an e-ticket is available. (Longer lead times apply for a paper ticket.)”. Surely I’m misreading this - does this really mean that we would have to wait until 3 days before we want to fly to book our tickets ?

This is my first post here so sorry if I have made any faux-pas or asked any questions that have already been answered somewhere else on the site

No! You can book up to 3 days before departure. Note that Oz award tickets are hard to come by, and have to be booked well in advance, ie. 12 months in advance. Even then, you may struggle to get the dates you require.

Cheers,
Rick