'C' racers on Zwift are mostly sandbagging Cat. 3's. They fly. I would, like you, have to be at it a few times to figure where to lay it down and where to sit back and cruise.
With a max. Wattage of only 523 you either didn't sprint or just stayed on cruise control throughout the race. A steady 250 to 275 on every segment...nice work! Flat sections were fast. The nice thing about your race was that in 46 minutes you got a better workout than I got in an hour and twenty minutes climbing 1300' over 23 miles in a 25-30 steady wind with 51 MPH gusts. You averages 24 MPH...typical race speed...while I fought my way along solo through that hurricane at 15 MPH.
Anyone that disses indoor trainer workouts hasn't been on a smart trainer in a live race.
I watched a few of the top riders on Zwift race and those speeds are pretty much 'pro'.
I hate indoor training and if I am forced to do it another year I'll be on Zwift.
The workout you get as far as time efficiency is unmatched. At that time of day, it would be 20 minutes before I even got outside traffic areas and could start to do some real work; or I would be confined to a riverside bike path and have to dodge joggers and dog walkers that time of day. Even VF park is pretty busy with commuters.
And yes, you get really great data. After this race, Zwift suggested that my FTP should be raised. That's nice that its all automatic and I adjust my training levels accordingly.
That ride was supposed to by a FTP training ride (2 x 20), but I saw the race scheduled and figured I could jump on and stay motivated better than just logging some of their pre-canned workouts, which are great but a little boring. And yes, after hours logged on trainers within the sweet spot, i am the proverbial human metronome.
My concern starting out in this "race" was that I would burn too many matches going out too hard too early. On B and open rides, I basically get gassed halfway through just trying to hang on and closing gaps. In many of these races, you have rabbits and CAT 2s who are going out way too hard for my pace. If I am in the 300 average for 20 minutes, then I'm going to get gassed over 45 minutes. On that race, I clearly held back and got stuck with a slower group, which caused me to pull too hard and too long at the front, and just didn't have enough recovery time to want to lay it all out there the last few miles or really try and pull away in a good hard sprint. There was nobody to really sprint against when I got close to the line.
Like any kind of racing, this does have its tactics which need to be learned. I clearly am not racing efficiently, but the training is pretty solid for this time of year. I wouldn't want a steady diet of it and I'm looking forward to spring, but I am surprised how motivating it is compared to simply staring at my garmin numbers for 50 minutes.
I am also taking some of these numbers people are putting up with a grain of salt. On a hilly course, if you lie about your weight, then the Zwift algorithm will allow you to climb at a faster rate than a heavier cyclist generating the same watts. Even on a flat course, if you overstate your weight, then you can race a class below because they are looking watts/kg. One of the racers in my area joined that race, and suffice it to say, he is a very fast CAT 2 who races in the season without the healthy layer of winter paunch he allegedly is reporting on his Zwift profile. (Looked pretty darn lean last time I saw him) He was in the upgrade group as well and absolutely smoked the course. This was a pretty flat loop so the weight issue was less a factor and he just motored ahead.
As a true test of a real race under real laboratory conditions, Zwift is lacking. As a fun way to get some of that race feel and keep your juices flowing, these virtual races are fun as hell. No crashes, no long time commitments riding to and from races, no fees, no flats. But a few percentages of inaccuracy across the field are real game changers in a race. If my PM is off a few percentages either way or somebody is reading really high, that's going to make a difference over 30 minutes. If everything is reasonably calibrated, than the race is reasonably fair. So far, my numbers are pretty close to what I can put out on the road. I always figured that if a person is insecure enough to cheat in a 'fun" competition like this, I can't let it ruin my fun.