I think it should be possible to be the best side without winning home and away against every single team. We're used to the number one side being so by a long margin, but there are a few shades in between.
Yea they can certainly be a best side without them winning home & away every single team. But although that teams doesn't have to have AUS 95-2006/07 - WI 76-91 invincibility, that team who doesn't win home/away everywhere needs to at least develop some years of performance where teams find it hard to beat them. # 1 in cricket is special accolade that has to be
earnt based on performances over a long period of time after you have proven you can/have the ability to win home & away fairly consistently. It is not to be thrown around losely to any team like IND currently who have not done the above or potentially England in 8 months time if scenario's go their but just have been playing consistent test cricket.
Even if one looks at those past great teams actual # 1 teams in test history.
- Windies 1976-1991
- AUS 95-2006/07
- Eng 1951-1958
- WI 63-68
Using the premise that you have to win home & away againts everyone to be the # 1. Only WI 76-91 & AUS 95-2006/07 had real daylight betweem themselves & the rest & won everywhere home & away (although WI of that period tecnhincally didnt win in NZ. But everyone except they were robbed in NZ 1980 to poor umpiring, while they drew in NZ 86/87, but overall this means nothing)
Look at ENG 1951-1958 for example. They where the best yea, but it wasn't daylight betweem themseleves & their competition. They won two very close Ashes series. While drawing in WI 53/54 2-2 (which was like playing India of the 90s of the time facing two quality spinners in Valentine/Ramadin on flat turning wickets & having to bowl againts a legendary middle-order in Weeks/Walcott/Worrell). Drawing in SA 56/57 againts a strong SA bowling side of Adcock/Heine/Tayfield. So they weren't faultless but did enough to be considered the clear best team by everyone who played againts them.
Since AUS lost their # 1 ranking at the end of the 2006/07 Ashes (although the flawed ranking system didn't take it from them until they lost @ home to SA 08/09). Since 2007 both India & South Africa have won 9 of the 14/15 series they have played in:
South Africa
India
So what we have is India & SA being the two more consistent teams in test cricket since AUS decline (this is why i dont understand how the ranking systems is giving IND a edge over S Africa currently). But none of them should be called number # 1 because they have failed to show they can win everywhere - they even right now as the best two teams. SA slipped up in India twice (2008 & 2010) & lost to AUS @ home), which is why the lost their # 1 ranking. While IND have drew in SA recently & have yet to win away to full-strength ENG, AUS sides.
Until some team proves superiority. We will have & will continue to have as it has been the case in post war test history at the end of any era of the previous great teams # 1. A jostling match until a proper # 1 occurs. Which would be good for test cricket if no such # 1 occurs again for a while, since that would mean overall test cricket will be very competitive.