Interpreting the 3-minute test results

My goal of this post is to get a peer-review / second opinion on my next steps in training.

With the goal of improving my > 60 minute performance beyond last years max, i think that i should change my focus to longer sub-maximal intervals to increase my critical power. Do you concur?

Testing:
I’ve performed two 3-minute tests, 3 months apart. Both tests where performed on the indoor trainer. The blue line is the first test in January. The orange line is early April. (watts on the y-axis, seconds on the x-axis)

The data analysis:

I conclude that my peak power output improved significantly, as did the drop-off in power… and Critical Power is roughly unchanged.
Before you ask: the non fluid orange line is the result of shifting gears in an attempt to keep cadence optimal. Both tests started in the same gear.

Training; during the last three months i moved my training away from public roads and onto the skating track. This means that every lap is an interval, as the power output to maintain constant speed is much higher in the corners. An HR zone 3 (out of 5) training results is 216 watts on the straights, while cornering power is 343 watts.
I think that this training explains the increase in peak power while CP is pretty much unchanged.
(a cool detail: according to my calculator i burn through W’ in about 100 laps…which is exactly how i experienced it during my last training :D)

Changing my training back to the road with longer sub-maximal intervals, should give me more constant power in the Type IIA muscle area, resulting in a higher CP.

What do you think?