Are you saying there are people who don’t wash their socks after a ride?
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Socks was a great topic. I was shocked at how different the results were between the two brands. Or the placement and length of bottles and bags.
Organizers REALLY need to end the silly practice of putting a number plate on the front like a 1970s motorcycle. Drives me nuts and impedes hand placement on the tops.
I would also like to hear the difference in other simple things like saddle/bar drop, angle/length of your gps, bar width/hood height/angle, flappy vs tight jersey (did you see his shoulder flap?!?), gloves vs. bare hands, slicks vs. knobs, etc.
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I would have liked to see the factor vs say the crux in the tunnel.
To confirm what I took away.
40mm tire
water bottle back pocket
larger seat bag
aero bars
aero helmet
aero socks
That seems to be the best combo
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@ABG I would say that is consistent with what I’ve been telling the forum for a while…but also Dylan is not telling you the whole story. 
As I’ve said in the past, the Rule of 105 is real but it matters most at higher yaw angles. If you take wind tunnel data into a block headwind you’re going to think tire width doesn’t matter that much. If you take wind tunnel data at higher yaw angles you’re going to think tire width is something that definitely has to be considered.
In a gravel context riders usually default to a wider tire because road surface hold primacy. I agree with that…EXCEPT…if you’re going to be on hero gravel and you can see critical crosswind portions of the course, don’t do it. Pick the 35’s. Trust me, it can make a difference.
I too would love to see how the total system gain differs from the individual gains. I asked years ago on ST and basically the answer I got was aero gains are not cumulative. Perhaps @RChung or someone in aerodynamics could explain which gains are stackable (cumulative) and which are not and why? I suspect you are close in your thought process above…
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On hero gravel I have ran a 32mm road tire, and was really fast. Issue is what 32mm tire would you run since a proper gravel wheel will have that tire balloon out?
I thought the same thing about yaw. I want to see what an aero gravel bike does at a yaw angle vs a non aero bike. I know some of the tube shapes dont matter with a head or tail wind, but at 10degree yaw it has to make an impact i would think
I want to see the aero impacts of the bike caked in dust and mud.
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All of these results have to be taken w a grain of salt. BikeRadar just did a wind tunnel testing like this and found an aero helmet to be more helpful than Dylan did (also a different helmet on a different person), but also found aero socks to be of almost no help. All of this is highly dependent on the shape of the person, riding position, etc…
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Isn’t the rim profile and width (affecting the tire profile) going to be a bigger difference in aero than just looking at the tire size? Someone out there has a bike & rim combo that would be significantly more aero with the 40mm tire than a 35/32 or whatever smaller tire.
Me too, especially with all this aero sock back and forth. Tell me what happens 20 miles in when you’ve got dirt, dust or mud caking the trip lines of your more expensive and probably less comfortable socks.
Grain of salt is so important with all this, but that doesn’t get YouTube views 
He says over and over that ymmv considering conditions, speed, rider, etc. What more do you want?
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Of course if you want to hit almost 90 mph on the flat
“Cyclists from around the world will gather on State Route 305 outside Battle Mountain, Nevada in a quest to break the human-powered land speed record. The record currently stands at 89.59 MPH (144.17 KPH).” (IHPVA website)
You want to go ultimate aero for your bike. All about minimising the air pressure differential between what’s in front of you and what’s behind you. It’s the lower pressure behind causing the drag, hence diminishing returns.
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Such an overlooked point…an extreme example is when I put my bikes on hitch rack. I can literally feel the difference in drag and my MPG goes down about 4mpg.
Which is why elongating the bike/rider with things like seatpacks and maybe bottles in a jersey pocket can be better aerodynamically, if you get the shape right. Would have like to see testing with a triathlon-style bottle behind the saddle. But then I also think that most of these aero gains by stuff at the back of the bike are being compromised (superimposed?) if there is another rider behind you.
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I suspect an issue here is that a) Dylan’s videos are meant to be polarizing, though this hardly seems like one of those and b) some TR loyalists are still upset about his SS video. As you state, he’s quite clear that YMMV, but it seems that’s not enough for everyone.
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I’m feeling really inspired after reading this 
I’ve done 100 mile races in aero socks and never had a comfort issue, so for me it’s one of those things where there’s no downside (and it’s not particularly expensive in the greater scheme of things) so I may as well do it even if the upside is somewhat unproven or debatable. Similar with aero helmets, my aero helmet is comfortable and doesn’t give me overheating issues (possibly because I’m in UK so never gets all that hot anyway!) so I may as well wear it. YMMV.
Tyres are obviously different, there are downsides to going narrower so that’s more about looking at the course, how you’re likely to race it, whether you’re targeting a result or just a finish, etc.
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If you look at the two baseline helmets, I think you will find the difference…Bike Radar used a Lazer Genesis as their baseline while Dylan used a Kask Protone, which has always been a “semi-aero” road lid. The vents are only on the front and when you drop your head, it is a smooth presentaiton to the wind. The Genesis is a pretty airy helmet across the board and likely not too aero.
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Hello!
I am that guy, 35mm tires blow out to 39mm on a OD 40mm rim
Setup
Pirelli Cinturato H 700x35
NXT45AGX-Z Rim (30mm ID, 40mm OD, 45mm depth)
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So my takeaways… run my half frame bag (empty), top tube bag, 2-1L bottles, my hip pack, and rock my inner bar grips.
That way, I might negate the watts I’m losing wearing a tank top, 2.1" tires, and unshaved legs. 
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