OP here, and this thread blew up more than expected. Went for a 140km group ride today, 30kmph, good tempo.
All intentions this morning were to ditch the bag and stuff the pockets. But as soon as I got my aero jersey on I felt even less pro than I did with a bag.
I quite simply hated the feeling of stuffing my pockets.
Left the house with banana, phone, gel and bar in pockets. Tube, repair patch, gas, multi tool, spare gel and bar in bag.
Phone and credit card in a ziplock goes in my jersey pocket on the right.
I have learned to skip carrying tube and co2. It’s been years since I’ve had a flat. On the off chance that I do get a flat, I’ll be Uber-ing home.
What happened there? I accidentally unscrewed the valve head from a canister I thought was empty once and really hurt my fingers. Can’t imagine a fully compressed one going off…!
+1
I’ve been using mine on the road and also on the MTB. I’ve got a 29er but have a 27.5tube as an emergency spare and it fits fine in the bag along with CO2 and multi tool.
I’ve been researching what to get for a second bag but I don’t think I can go past getting another one!
The HORROR!
It almost warrants a whole thread on things we do that make no logical sense but we do them BECAUSE.
Have to agree with @jsteelfex and @sryke, pros on long training rides often carry more than most of us on the bike. Not uncommon to see a seat bag big enough to hold 2 tubes and an old school long Silca or similar frame pump (though those don’t fit on a lot of modern frames very well). Phil Gaimon and Adam Myerson come to mind. May not “look” pro per the rules, but when you take all that stuff off on race day your bike feels super light!
Bcuz marginal gains bro.
I had to mess around with where it fits best, but I am using a Wolftooth B-RAD 2 on my Cannondale CAAD-X. It allowed to me install 2 Specialized Zee Cage II’s with a Specialized SWAT box. I like the setup enough that I am thinking about doing the same thing on my road bike.
(The attached photos are from the trial and error installation phase.)
I also use the Lezyne Caddy. Fit in my jersey pocket perfectly.
15748206562&hydadcr=9376_9531499&keywords=lezyne+caddy&qid=1566832921&s=gateway&sr=8-1-spons&psc=1&smid=A17U4P8R5Y7PAH&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzOE9JSVZCMDNFWlhDJmVuY3J5cHRlZElkPUEwOTI2MjA5NlhKUENDSU5DRk45JmVuY3J5cHRlZEFkSWQ9QTAzNTcxMTIySFFPMjQ5V0RDNkZGJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==
which size?
Medium.
I had a saddle bag once about 10 years ago but took it off and haven’t looked back. I personally don’t like the extra visual bulk and the rattling. To each their own. I’ve been riding everything from 30 minute town spins to centuries and coastal rides and have never wished I had one.
But hey, nowadays the more bags one has on a bike, the cooler it is, expecially when paired with aero jerseys 
i have to say, i have never heard of that proverb before. i am chinese. 
I like that setup, might just have to copy it.
x2 on the Lezyne Caddy. I have a small which holds 1 tube, 1 tire lever, 1 co2 and a small infiltrator (its a very tight fit though, I’d get the medium next time).
One thing to grab pre ride instead of 4 things. I still carry a saddlebag too as a backup for multiple flats but the Lezyne pouch has become my “1st flat” kit as it is so easy to get to.
It recently occurred to me that a USAC silver membership includes a 24/7 roadside assistance number. So if you have the time to wait you can ditch the saddle bag and just put the USAC roadside assistance # in your cell phone.
https://www.usacycling.org/resources/insurance/roadside-assistance?
3 pockets on the jersey.
Left hand is all food
Middle is all tools n tube n patch kit
Right hand is just phone.
ID and CC go inside phone case.
Trash is to be ditched into middle pocket.
Well, no wonder. China is a big place! 
must be from the area where they do the really funky stuff like ride without saddlebags.
