Viking Warrior re-visited

Jon:
Had a gap in my schedule before the training session in Parc Ciutadella yesterday and decided to revisit the Viking Warrior 15:15 protocol for the first time in more than a year (did a little of it at the RKC-cert but that was just about 20 min or so). It took me a while to complete it when I worked with it last autumn and I remember it as fairly gnarly. It is good to have something to return to and compare your present level of work capacity.
15 seconds of work and 15 seconds of rest doing 8 snatches/interval with a 16 kg bell.
I totally blew it out of the water! Well perhaps not totally. After a little less than 30 min i quit since I started to get a blister under my left pinky finger. At this point however I felt nothing. A little sweaty of course but heart rate barely raised at all and no problem what so ever of holding the cadence.
It makes me think why. How can something that I struggled with a little more than a year ago be so easy today? I can think of a few anwers that can be combined:
I did a lot of snatching up to the RKC cert to ensure that I would pass the snatch test. During last spring I safetly did 100 snatches with the 24 in under 4 min.
Since the RKC cert however I have barely snatched at all except for a little very heavy snatching with the 32.
My cardiovascular capacity got a real boost with the first 4 months of training at Crossfit Nordic. I think those combined with the training leading up to the RKC pushed my work capacity (especially cardiovascular and muscular endurance) to a level that I have not reached before. My long distance running capacity (8-10K) has been a lot better but that was a long time ago (10K in under 35 min when I was 19 - "If you are not now, you never were") and getting times around 40 min on 10 K really isn't about cardio, it's about running, running, running. Since summer I have had very little focus on cardio.
Kettlebell Muscle has made me stronger. I imagine that especially my trunk strength has increased quite a lot the last six weeks. That should make it easier to snatch a lot.

After I completed the 15:15 protocol with the 16 kg last autumn I started to play around with the 24. I don't think I ever completed more than 10 min. Now I think I'm going to try it with the 20 kg. It feels like it just might work.