If McLaren have serious aero/chassis problems why would they do a low fuel qually lap? it doesn't seem to make sense, surely it's better for them to do longer runs, get some real data on how the car handles?
McLaren were at Barcelona for 4 full days. I'm pretty sure they tested all types of fuel loads and settings. Remember re-fueling is still permitted, so it makes sense to test all fuel loads from full tanks to empty, as it gives the engineers an idea of how the car performs over different fuel loads.
Furthermore, I'm pretty sure McLaren would want to know just how fast they are in comparison to the rest of the field, so would've tried a few glory laps. It's better to do this in testing (and have the test data, to take back to the factory), than to go totally blind into the Australian GP without a clue how the car performs when set-up for aggressive qualifying runs.
The more set-ups and fuel loads a team tests, the better it is for the team and for driver, so that they will have an idea of what the car is capable of, which in turn should allow the team/driver to set the car up quicker, for qualifying/race runs on GP weekends. Going into a GP totally blind, is a VERY bad idea.
Based on past seasons, the teams who do the most testing miles, tend to be in the best shape for the start of the season (probably due to the fact that they have a lot of data and know how to set the car up).
But of course we won't know for sure till Melbourne, Personally I think McLaren might be somewhere mid-field rather than right at the back, but who knows...
Agreed.