Joaquin has said that the reason the file took so long to get to us is because his server choked on the size of the original file. Accordingly, I've taken the liberty of putting the file I got from him --> here
<-- in original PT .csv format. Joaquin says that the file includes a *lot* of other rides that precede the the climb of La Morcuera and that the relevant interval is marked as ID=1. That occurs about 175km into the file. That segment is 28:35 minutes and 8.76km long, with a mean of 359 watts.
However, the data are very, very odd. Perhaps the best thing is to show you a few plots of the data, with the preceding 8km from the file to show you the difference. In each panel, the data to the right of the vertical dotted line shows the climb.
The fourth and sixth panels may need some explanation.
The fourth panel shows the difference between the reported distance (8.76 total km) vs. the distance calculated from speed and time. As you can see, the cumulated error over the first 175 km of the file is essentially zero. However, the distance calculated from reported speed differs by more than a kilometer over the ensuing 8.76 km. That is to say, the speed for the climb doesn't match up with the distance.
The sixth panel shows the estimated gear ratios used. Gear ratios are calculable either with speed and cadence or, if one has a Power Tap, by watts, cadence, and hub torque. The point is that gear ratios are quite distinct and discrete, as you can see from the left side of the panel (or for the preceding 167km, if you calculate and plot them). However, the gear ratios for the climb data don't fall into neat rows.
The second panel shows speed during the climb. Joaquin was able to maintain speed in a very small range over the entire climb, with sudden jumps and discontinuities. Despite the jumps in speed, Joaquin's HR was a very steady 182 bpm.