I think it would actually make the game closer for shorter. In that example there with the current 50/50 format, you've probably seen about 55 overs worth of cricket where the game could still go either way. Just say they go with the 25/25/25/25 format, and India makes 2/150 in their first 25, and New Zealand is at 3/20 in the first 5 overs of their first 25. In this case, you see around 30 overs worth of cricket where the game could still go either way, in comparison to the 55 overs in the current 50/50 format. Although, there may be other permutations that means the game stays closer for longer in the 25/25/25/25 format.
The Zimbabwean pitches weren't particularly bad wickets, not green seamers or anything like that; just tacky. Bad balls can still go for four in these conditions, but it is much harder to drive on the up while it is tacky. In those cases, the entire first innings took place before midday, so it wasn't a case of getting through an hour and making up for it. Batsmen were able to get used to it, but any time a wicket fell, it put a lot of extra pressure on the new batsman. Collapses grew for a range of reasons, but the main thing is that the team batting second was not tested in remotely the same way, when the ball was coming on much better in the afternoons.
Ok, at what point is it no longer cricket?
They're only going to succeed in alienating the on-the-fence fans who are undecided between Twenty20 and ODI cricket. As someone said earlier, some of T20's beauty is in it's simplicity. It's pretty straightforward (apart from the free hit rule). You bat for 120 balls and whoever has the highest score wins. ODI cricket started out like that but we've seen so much failed experimentation (remember the super subs and all that nonsense?) and T20 has capitalized on the viewer market.
It isn't really, though. Splitting up ODIs is a step in the direction of Test matches, and the fans that ODI cricket are losing are not Test match aficionados--they're T20 ones.And in my ideal world you'd have some kind of ODI/T20 combo to lose one format, clear up the international schedule a bit and still keep crickets new fans. This 40 over split innings stuff is a step in the right direction for me.
It's marketable because it's simple. There's no excessive rulemaking involved that makes the game confusing to a new or passive fan. For example, my mom followed the last IPL closely whereas I doubt she could explain to me what the follow-on rule in Test cricket or the PowerPlay rule in ODIs means. Splitting ODI cricket into two innings is not going to make it simpler, because there is going to be a whole host of new rules that come into effect to plausibly effectuate that split--for example: How will bowling spells be handled? How will the new ball be handled? Will there be a follow-on rule like there exists in Test cricket? How will rain-interrupted matches be decided? What of power plays? What about injured players--can they come back and play after the break? How about player averages? Etc.To me T20s been successful because it's short - not because it's simple. It's easily accessible. You can watch a whole game at the ground/on TV without wasting a day, you can bring kids along as they only have to concentrate 3 hours instead of 7 or 8.
I agee with Sohum here, Twenty20 is so simple to explain because I just present it as
120 balls or 10 outs per innings to score as many runs as you can and 1 innings each only,
anyone who knows a thing about baseball can instantly grasp the concept as many of my friends have.