Could you combine a Hatfield-Finsbury Park, with a Zone 1&2 period
travelcard? Would this do the trick for you?

I can, but it's £36 more expensive (basically, the price goes up the
more stations on Wagn you use) and I don't then get the benefit of
buying tickets from Bounday Zone 6. I presume a Zone 1-6 Travelcard
still serves as a Network Card for 33% off certain rail fares?

I've opted to wait now until renewal in December, because it will be
messy trying to change tickets part way through. I'm unlikely to save
much (less than half of £220 as I've had the ticket 7 months). I'd
also need to start a whole new year on LUL, and if fares go up in
January 2006 then I don't want to have 6-7 months less to benefit from
the 'old rate'! It's never that simple is it!

Thanks for all your comments. I hope that it has prompted other people
on here to consider the same thing and save a few quid!

Jonathan