The tires have destroyed the hierarchy of F1 and made mediocre teams like Williams and Sauber equal to top teams like Red Bull and Mclaren. Every race is a random lottery because the tires are so inconsistent.
Pirelli has effectively turned F1 into GP2.
Ok, this needs to stop. Yes the tires are more inconsistent, yes. But each race being lottery?
Firstly, Red Bull have more than double the points of Sauber & Williams combined - so you can hardly call them equals. Secondly the leading driver is also widely considered the best driver on the grid in what seems to currently be the 2nd best car.
So im guessing when your talking about them being equals you are referring to Perez's 2 podium finishes & Maldanado's race win.
Saubers have looked fast all season & last season they got a few top 5 finishes (ignoring penalties), so you can hardly say this hasnt been coming.
and for Williams, well they seemed pretty quick at the start of the season & probably would have got a few podium finishes if they had better drivers. And with all the changes in staff they have made over the summer break its not surprising their car has improved since last season.
As for McLaren, who you now considered equals with Williams - its entirely they own fault - they cannot blame the tires for how far they have fallen since the first race of the season. But even still they are only 10 points behind 2nd place.
So, the reason it must be considered a lottery is the 7 winners from 7 races, well its very likely that the season will finish with no new winners. So really a whole season with 7 different winners isnt really that spectacular.