If there is one rider in the entire MotoGP paddock who recalls the strange case of Dr. Jekyll and Mr. Hyde, it is Marc Marquez. Around the paddock, speaking to the press, at public appearances, the Spaniard is soft-spoken, polite, friendly. When he speaks, he speaks only in commonplaces, his media training having expunged any trace of opinion or controversy from his speech (in either English or Spanish). Put him on a bike, however, and the beast is unleashed. He is merciless, in his speed, in his ownership of the track, and in his disregard of anyone else on the track.

So it was unsurprising that the Spaniard should find himself in trouble once again. During the afternoon practice, Marquez slotted his bike underneath an unsuspecting Simone Corsi going into turn 10, sending the Italian tumbling through the gravel in the process.

The move was reminiscent of the incident at Motegi, where Marquez barged past Mika Kallio with similar disregard for the consequences, but unlike Motegi, this time Marquez received a penalty from Race Direction, for contravening section 1.21.2, a section Marquez by now must now almost by heart. That part of the Sporting Regulations which governs ‘riding in a responsible manner which does not cause danger to other competitors’. For his sins, Marquez is to start from the back of the grid on Sunday, regardless of where he qualifies.

The punishment has been coming for a while. Race Direction has been working this year on taking previous behavior into account, and that, above all, was the reason for Marquez to have his wrist slapped.

The list of incidents involving Marquez is long: starting with the collision with Thomas Luthi in the very first race at Qatar; the clash with Pol Espargaro at Barcelona, causing Espargaro to crash out; the collision with Kallio at Motegi; and now this incident with Corsi at Valencia. There were numerous other minor incidents in which Marquez featured, the Barcelona incident, for example, coming at the end of a race which had seen a fair smattering of other questionable moves.

When Casey Stoner was asked on Thursday about the key to his speed through Turn 3 – now renamed Stoner Corner in his honor – he refused to answer, saying only that he might tell everyone after he had retired. To anyone watching Stoner scorch around that corner and the rest of the track, the secret was plain to see: the Australian is completely in his element, totally comfortable and confident in every move he makes at the circuit.

Stoner left thick black lines round most of the left handers at the circuit, including daubing them all over the inside of the kerbs at Turn 3. It was a display of mastery that left even the injured Ben Spies in awe, watching at home on the computer. “I gotta say without a doubt Casey Stoner does stuff even GP racers watch and scratch their head at!” Spies posted on his Twitter page. Stoner ended nine tenths of a second up on second-place man Dani Pedrosa, the only man to dip into the 1’29s (just, his fastest lap being 1’29.999), and the only man bar Pedrosa to hit the 1’30s.

The main protagonist in Friday’s action was the weather. Like a hormonal teenage girl, the rain simply could not make up its mind whether it was going to fall properly or not, light drizzle blowing in for ten minutes before blowing out again five minutes later.

Hormonal teenage boys, it should be noted, know exactly what they want, and apart from the obvious, what they want is the opposite of whatever they have just been told. The weather left the track in that awful half-and-half condition, too cold and damp for slicks, too dry for wets, and the track conditions left the MotoGP men mostly sitting in the pits.

Dani Pedrosa explained it best. “Too wet, so you cannot push, so the tire cools down immediately after you go out, and in or two laps you have to stop, because there is no temperature in the tire. And with the wets, it’s completely the opposite, the tire is immediately out of the working range, and one or two laps and it is gone.” Even in the short period you could go out, there was nothing to be learned, Pedrosa said. “If the tire has too much temperature or too little temperature, the bike feels completely different. There’s no meaning in going out.”

Friday would prove to be an eventful first day of practice at Brno. Thrills, spills, and plenty of flag waving, mostly of the red variety, as crashes played havoc with the day’s schedule. It started in the morning, during FP1 for MotoGP, when Valentino Rossi ran wide in the final corner, and his rear wheel kicked up a couple of sizable rocks. The rocks hit Dani Pedrosa, on the top of his foot and the front of his fairing, destroying the screen. How fast was he going when he was hit by the rocks, one intrepid reporter asked? “I don’t know my speed,” Pedrosa quipped, “but the rocks were going like they were shot out of a gun.”

And they weren’t small rocks either. Asked what size they were, Pedrosa held up both hands, touching thumbs and forefingers together to make a circle. “Like this,” he said. About the size of a grapefruit, then. Pedrosa said he had been worried that the impact had broken a bone in his foot, and the Spaniard was limping visibly as he got off his Repsol Honda, but the pain subsided as the session continued, reassuring him that there was nothing broken, just banged-up and bruised.

MotoGP has a love-hate relationship with the Indianapolis Motor Speedway: most of the paddock love the place, the rest hate it. The way those feelings are divided is what is really interesting, though: the admirers of the track include most of the media, the teams and many, many fans. Those that hate the track are a small but well-defined group: anyone either wielding a camera or a racing a motorcycle have very few kind words for IMS.

So why the schism? It really depends on what you are doing at the track: the circuit has some of the best facilities of any circuit the MotoGP circus goes to all year, making the life of the media, the teams and the fans exceptionally easy. The photographers, on the other hand, hate the track because of the fences. As a circuit that mainly hosts car races, there are high chain-link fences all around the circuit, to prevent debris from wrecked four-wheelers from flying into the spectators.

At a few selected spots on the circuit, there are openings in the fences for photographers to poke their lenses through, giving them an unobstructed view of the circuit. There are lots of photographers and relatively few camera holes, leaving gaggles of photographers gathered around the available shooting spots like narwhals around a breathing hole in the arctic icesheet.

Hector Barbera will be forced to miss the Red Bull Indianapolis GP, after suffering a back injury during the morning session of Friday’s free practice for the MotoGP class. Barbera suffered a nasty highside at Turn 16, his rear wheel appearing to catch on a section of track which appeared still to be dirty, and in the ensuing crash, Barbera landed on his neck and fractured three dorsal vertebrae, D5, D6 and D8. He was taken to the local Indianapolis Methodist Hospital, and has been ruled unfit to race.