So, if it was me, and I’m thinking I might fail the workout I’d press one button once to bias the workout down by 1% and hey presto I’m OK. I’m still within half a handful of watts of my target. No way there’s any difference in any adaptations the workout will (hopefully) deliver.
I know there’s an argument that I shouldn’t have to, but the workaround is there, and it’s easy.
Yes, it is really frustrating. Zwift has accepted that there is a bug (“This topic has been resoved”) - and does nothing. Hopefully, getting rid of the hardware stuff now sets free some resources for bug resolution and QA. Unfortunately, there’s still no real competitor, thus we stay here - and sure enough enjoy the good features of the platform.
Interestingly, we seem to encounter some AI bots (?) in this forum, those, who simply don’t care, who don’t have a clue about the consequences of the bug, who even seem to ignore their fellow customers obiously struggling with the imprecision,
AND posting an opinion anyhow
If only my posts were sufficiently well-crafted that someone might think they were generated by an entity with intelligence. 
There are plenty of Zwifters who have don’t do FTP intervals at 300W, maybe it’s 200W, 150W or even less.
5W increments are a lot tougher on them.
This was a feature some time ago, and it was taken away for no apparent reason.
Agreed. I took a guess at the FTP of the person I was replying to. It’s undoubtedly true that the +/- 2 or 3 watts is more significant for Zwifters with lower FTPs.
It’s daft. I have no idea why they did it. I’m just trying to provide a) a sense of perspective and b) workarounds until they unbreak it.
@evan-zwift Anything you can share on this issue?
Are the ramp section durations still also an issue? I think only changing every 15 seconds by large wattages going up or down from starting point to your target, instead of (why not?) every second by a smaller wattage amount difference.
That’s exactly the problem! Adjusting by 1% can have zero effect if 1% doesn’t get you to the next 5W level. I discovered the problem when I was looking at my data and realized that bumping up 1% didn’t actually progress my last few workouts.
Imagine you’ve got erg mode at 100W at 100%.
Decrease to 98%, still rounds to 100W
Button press → 99% – nope, still 100W
Button press → 100% – nope, still 100W
Button press → 101% – nope, still 100W
Button press → 102% – nope, still 100W
How does this make any sense? I get that some people don’t care and some people aren’t effected, but there’s just no logical reason for it to be this way.
Correct, the changes are only every 15 (or 30, 45 etc. depending on the slope of the ramp and where you are in the ramp) seconds, and then they go up or down by no less than 5 watts.
Edit: On my cooldowns after the end of a VO2 max workout I often watch for the 15s increments for the ramp to drop down by 5W, and I get sad if the 15s time goes by with no drop 
I have noticed that when I look at the Companion App while doing a workout that the app may say “173 watts for 30 seconds” but the main screen has me at "175 watts for 30 seconds).
The ZCA will move in small, less than 5W steps, but the main Zwift screen moves in 5W steps.
Another thing I noticed today while doing a long Z2 interval is that which cog I was on affected my power output. I tend to shift gears a few times during the workout to no wear out one cog.
When I was on a larger cog, my power was at 178-179 watts when Zwift was calling for 180.
I moved two cogs smaller, and my power went to 183-184 watts (my readings were from my Garmin, linked to my PM pedals, which control my Kickr). I checked thos several times throughout two ten-minute intervals, and I got consistent results. I use ERG exclusivley for workouts.
It’s stupid and irritating I agree … but in your example why are you progressing intervals at 100 watts, Steve? I get that it maybe makes the maths easy, but it exaggerates the scale of the problem if that number is actually recovery watts. It doesn’t overstate the problem, of course, if a Zwifter’s FTP is nearer 100 watts and so the delta caused by the rounding is a significantly greater proportion of their FTP.
How does it work in terms of button presses if your intervals are at, say, 270 watts but “should” be at 268 watts?
I did Build Me Up last year. It bugged me a bit that the targets were “off” by a couple of watts so, on one workout and just for fun, I did the first half of my sweetspot interval at the rounded down watts, and then the second half at the rounded up watts. NERD! 
I didn’t bother doing that again. I couldn’t really feel the difference, and it’s sweetspot so the precise intensity matters much less for progression than Time in Zone.
Apologies. I know I’m in danger of coming across as argumentative. Not my intention. I do hope they unbreak it. It’s causing annoyance - even if I think some of that annoyance is slightly misplaced - and for that reason alone it should be a priority.
The Thing is the inconsistency.
Zwift itself uses rounding. The values displayed in the workout screen of companion app don’t get rounded. Its pretty easy to spot and monitor.
So the real issue is just to send the correct value to the trainer. It is already there. Remove the code lines that round the value to +/- 5W steps.
Ramps are completely useless now. The subtle change was excellent and thats what ramps are for. Increase or decrease power so subtle. The +/-5W steps are noticeable in the legs and not what was intended by the workout creator.
Also imagine VO2 Max Intervals 3x10 reps and each rep gets 1% easier. If your FTP is e.g. to 230W, then you have 300W on the first rep, second rep is still 300W although it should be 298 or 297W, third rep would be ~295W.
Actually you’d do 2 reps with 300W but the second rep should be easier, which it isn’t. This already can sabotage your workout and training goal.
Is this planned to be fixed? I’m one of those with a lower FTP, 196 right now. When I’m doing workouts given to me by my coach, the Zwift app coaches my Target number. My current FTP is 196, I fluctuate between 195 and 205 depending on my training and where I am in the season. When I’m supposed to be holding zone 5 for 3 or 5 minutes, every point matters. If I’m told to do 216 or 217 and my choice is 215 or 220 I of course don’t want to sell myself short. But at the same time that :20 is going to be a lot harder for me on my 4th and 5th interval then it needs to be. Why is there not an option to turn off the rounding. Some people might be fine with surrounding, but clearly many of us aren’t. 
It’s embarrassing that not only has this not been fixed yet, but it’s yet to be acknowledged.
It was acknowledged
It’s probably breaking something in their code / caused issues with some new feature.
Instead of a proper fix, they decided a hack job was the answer.
When will this bug be fixed? It confused me for a while already.
< sarcasm on > Probably never, staff is fully occupied by figuring out a new XP rewarding system! < sarcasm off >
It’s a shame.
Over two years now… It’s a real shame… 
Any word on when the future may come for this?