Forecasting form around Spa is effectively the same as trying to forecast the mercurial weather of these valleys with their own micro-climate. Both Friday practice sessions were adversely effected by the rain, but there was a 25-minute period in the middle of FP2 where pretty much everyone got onto slicks.
That small window suggested the usual three suspect teams - Red Bull, Ferrari and McLaren - were set to fight out the destiny of the race again, but the form between them did appear to vary according to the weather conditions. The weather forecast indicates qualifying and race should be in the dry - but, as ever with this place, don't bet on it - in which case, Red Bull looks the strongest, albeit not by much.
In the wet, the picture is less clear.
Red Bull's Mark Webber set the fastest time of the day with his single lap on the soft option tyre before heavy rain arrived in the last half-hour of FP2. But this was just a couple of tenths faster - around a very long lap - than Ferrari's Fernando Alonso on the same tyre and 0.5s ahead of the McLaren pair, Jenson Button and Lewis Hamilton, their times also set on the softs. Sebastian Vettel's Red Bull set the best medium-tyred time, around 1.5s-off Webber on the soft.
As a measure of how much faster the option is than the prime around here, Vettel's time was actually slower than the soft-tyred Mercedes, Sauber and Force Indias.
If it's a dry race and the soft holds out as well as expected, a three-stop race with a very short final stint on the primes looks the favoured choice. In such circumstances Red Bull looks favourite; not only is it marginally the fastest but the car is the fastest at the end of the long straight before Les Combes. Red Bull can then follow this up with being quickest through the fast turns of sector two - by as much as 0.4s.
Fernando Alonso looked stronger in the dry © sutton-images.com
It would appear the team has enough downforce in hand over the Ferrari and the McLaren to be able to run less wing. Also, the difficulty it had in getting its tyres to switch on as quickly as the McLaren's - crucial at both the previous race - should be a less of a problem on this track with its long lap and long high-speed corners.
The DRS zone between the top of the hill and the entry to Les Combes will, however, make it difficult for any of these three cars to break away from the others and so a close race should be in prospect regardless of the formidable combination of qualities of the RB7 around here. If a Red Bull can lead into sector two on the opening lap, it might just allow it to pull out of the DRS zone by the third lap.
McLaren was trying its new rear wing - featuring a more aggressive DRS stall, but less efficiency in normal usage, more like the wings of the Red Bull and Ferrari - in combination with the old one. Both drivers and Martin Whitmarsh seemed to be favouring using the old wing, even if it will compromise their qualifying chances. It would seem these options present a conundrum for McLaren: do you qualify well and have good end-of-straight speed but less raw lap time pace? Or do you accept relatively poor qualifying and vulnerability at the overtaking spots for raw pace - very useful around the pitstops?
Ferrari has also brought new parts, including a rear wing tried in practice in Hungary. The long lap should help the car get around its sole remaining weakness of not getting its front tyres quickly up to temperature and there's no reason why it should not be a formidable tool here in the dry. The one difficulty it might face could be if the forecasts are wrong and it does rain either in qualifying or race. On the intermediate running Fernando Alonso was only fifth quickest, a long way from the pace of Button's McLaren which set the fastest intermediate time, though the Ferrari's time was set in slightly wetter conditions.
Underlining this pattern, in the dry running Alonso was less competitive on the medium than the soft (by around 0.5s relative to the other cars). But, as we saw in Valencia with this tyre, with a rubbered-in track near the end of the race, that problem can disappear. But you can be sure Ferrari will delay running on this tyre for as long as possible on Sunday.
McLaren look likely to revert to the old DRS wing for Spa © sutton-images.com
If it does rain, the McLarens look particularly strong. Button was the fastest of all on the inters - Lewis Hamilton didn't run during this period of FP2 - and seems very much on a mission, looking to continue where he left off in Hungary. The McLaren's recent ability to get instant tyre heat will be much more valuable in these conditions than in the dry here. This may be another reason why the team seem inclined toward the older wing, with higher downforce, in that this would lend itself better to wet conditions.
Don't bet on anything here. But the early signs might suggest Vettel/Webber vs Alonso in the dry (rather like Valencia) or Button/Hamilton vs Vettel in the wet.