very true. the upgrade path exists for a reason. jumping categories just because you can isn't the best approach.

His main point is correct though, while you CAN break bones in a bike crash, most leave you with nothing but road rash. I've crashed three times over the past year (one my fault trying to take the last corner of a crit at 30 when it should be taken at a max of 25 and riding right off the road, the other two not my fault) and have not broken anything.

Adding in my experience since it's somewhat similar. Used to race Xterra and 70.3s decently well (went to WCs for both), switched over to bike racing shortly after first kid. Now have 2 kids, aged 3 and 5, race bikes as Cat 2. But the catch is I'm pulling the plug after this year to spend more time with the family.

In general your fitness will get you through cat 5 and 4 pretty easily where you can ride away from the field. In the 3s you'll need race acumen, which you may or may not have, as if you miss the moves there is very little that loads of fitness will do for you. Especially if you're tall/big, people will wise up quick and suck your wheel at every race only to come around you at the end with a kick.

Crashing is definitely a possibility, but not a requirement. I've seen people hit the deck tons, and retire from racing as a result, whereas I've maybe ended up with minor road rash in a handful of falls over the past 4 years, so YMMV

But back to time commitments of 1 sport vs 3, I don't necessarily find bike racing to actually save you that much time as you end up racing a lot more (10-20 races a year) and the drive+race time of each (road races will be ~3hrs) eats up close to the entire day on many many weekends out of the year. If you want to trim back time and be competitive in a sport, I would recommend running (trail running maybe) instead.

The training is also a lot more grueling and intense than what one would do for tri's. Lots of over-unders, lots of sprinting when already knackered, etc. It got to the point that I wasn't particularly fazed about going OTF b/c I'v suffered more during training.

I should also mention that there's a psychological cost as well. Whereas there is more of a linear correlation between training and results in tri's, it's more of a crapshoot in bike racing. So when the results aren't there, one better be mentally tough enough to carry on. I had a whole season like that, when almost nothing clicked. Somehow the next season, I was racking up points and going OTF (and staying away) almost at will. Difference in physiological markers weren't actually too big, maybe 10 watts. In addition, there's quite a bit of time devoted to analyzing the course, analyzing the opposition, etc. Racing ITTs is so much less stressful in comparison.

one last note, perhaps a sort of caveat emptor. Two years ago, someone here was hyping a pro triathlete and how the latter was going to dominate as a road racer. This pro blitzed to cat-2 within half an year but then appeared to have hit a wall. Apparently didn't race at all since then.

Good point re: results vs effort put in being very different in cycling vs triathlon. Not including mechanicals and race incidents, sometimes you just miss the break or split and just like that, your race is gone.

In terms of expectations, like was mentioned there is a bit of an exponential curve to deal with. Getting through the lower categories to being a 2 is very doable for most fit/healthy/athletic people (IMO), but doing well as a P1/2 is something entirely different. Kind of like running a 5 min/mile vs running a 4 min/mile, or qualifying for a WC vs doing well at a WC.

Give it a try, it's fun and a good change in terms of team dynamics compared to the solo experiences of triathlon.