Last week's young driver test gave Red Bull and McLaren a controversial development boost - but bendy wing revelations in Abu Dhabi also saw teams hard at work analysing data back at base.
This year the young driver test session was split three ways, with Marussia, Williams and HRT running at Silverstone in July; Mercedes, Ferrari and Force India at Magny-Cours in September; and the rest of the grid testing in Abu Dhabi last week.
The original idea of the test, which was introduced when in-season testing was banned in 2009, was to give young drivers a one-off opportunity to try F1 machinery, as otherwise their only chance of sampling current cars was on Friday during a Grand Prix weekend.
Now, however, the top teams are openly admitting to using it for car development - and with Red Bull and McLaren in action and Ferrari forced to sit out having already used up their three days earlier in the season, it could have a major influence on the season run-in.
McLaren ran experienced testers Oliver Turvey and Gary Paffett for much of the three days - and the latter, at the aged of 31, clearly cannot be positioned in the young driver category. Red Bull did use less experienced drivers, but even they are talented enough to know how to run to instruction to enable the team to make steps forward.
Whether this is fair or not, right now it is how the rules can be played - and both teams grasped the opportunity.
McLaren tried out a new front wing which had significant changes to the inner front winglets, creating a much cleaner design more similar to that on the Lotus. Red Bull, meanwhile, tried out what appeared to be additional tubing on the rear wing, possibly to do with a DRS system.
Interestingly, both teams used the test to do some intense analysis on the flow around their cars using a large range of measurement equipment - developing an understanding that can help significanly with set-up and with learning how new parts affect the rest of the car.
The most obvious testing devices were aerodynamic pitot rakes, which are grids of tubes pointing forward into the oncoming airflow. These measure local air pressure at set locations and this data can then be related to CFD data to ensure the real and virtual cars match up.
McLaren used a very tight and heavily packed grid in front of the rear wheels to measure the flow around the rear of the sidepods, while Red Bull used a variety of grids, with a less densely packed one in front of their sidepods, a giant one halfway down the sidepod that rose to full car height and several inches outboard, and a more densely packed one off the bottom of the rear wing to measure flow out the diffuser.
Flow visualisation was also in use, with Red Bull using the traditional bright green paints and McLaren trying a light blue paint that is less visible to prying eyes and shows up its detail when viewed in UV light.
McLaren also ran with large struts mounted to the rear wing that held more pitot arrays out around the car. One set-up stuck out sideways and mounted a straight line of tubes above and behind the rear tyres while another was attached rearwards to measure flow behind the rear wing.
Finally, the McLaren also sported what appeared to be laser measurement sensors in the front wing area, probably used to measure deflection.
It was interesting to see them openly exploring this area - given the dramatic demonstration of Red Bull's flexi designs at the last race in Abu Dhabi.
A video showing the removal of the nose cone on Sebastian Vettel's car mid-race, after he had hit a marker board, revealed the yellow front nose section bending like putty - and given that it is connected to the stays that mount the front wing, that allowed significant movement in the front wing.
The nose was clearly broken due to the collision, but the rigid crash structure should not usually show such flexibility even when broken - and it suggested the team is very advanced in the use of materials in this area.
There is a variety of theories on why the particular nose part would be so flexible.
Firstly, a moving wing can give significant aerodynamic gain with the most obvious advantage being the flattening off under high load to reduce drag at high speeds. It could be that the bending nose allows this to happen.
However, it is at lower speeds and over the kerbs where Red Bull's wing is most interesting - as it appears to vibrate heavily, far more than any other car, and it also rocks forwards and backwards.
This initially would appear to be far from a benefit, as the stability of the front wing is crucial for aerodynamic performance. But ther is another school of thought on what Red Bull is doing.
It could be that they are using the wing to dampen the vibrational forces caused by hitting the kerbs in slow corners - allowing all the vibration to shake out through the wing while keeping the chassis of the car far more rigid and stable to maximise the downforce from the floor and diffuser areas - losing front wing aero, but gaining overall.
It could, in fact, be a combination of both, with the flexibility of the nose acting differently when different loads are in play at different speeds.
Whatever it is doing, though, it seems to be baffling the other teams.
Several rivals have developed detailed dossiers into the subject but the fact is Red Bull's designs pass all the FIA's legality tests despite clear dynamic flexing out on track - so the strict legality of the design is not in question.
Which is why everyone is so desperate to find out what they are doing and how to replicate it.
One theory is that there is an outer casing on the front nosecone made of a thin plyable material which sits with the main structural nosecone inside - and the outer casing can deform around the main structure.
Teams have been investigating flexible materials for years - but it always seems Red Bull are a step ahead. And it seems like it will take their rivals a while to get to the bottom of this one...