No Bag Security:
If you can fit your bag and contents into your pocket or reasonably in your wasteband, you're good.
If you can unpack your bag and have enough room to temporarily put everything into various pockets or socks, you're good.
Your bag cannot be showing in plain view. That's the main criteria.
Cargo pants are your friend today
You can openly carry phone, keys, &/or drink. As long as you can stuff whatever else you have (lipstick, sunscreen, cards, slingshot, etc) into your pants/bra/socks/etc without bulging like you're carrying bowling balls you should be fine going thru No Bag line.
Once you get into the park, you can repack your bag and carry on as usual.
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Interestingly there was 1 week early in the RoR madness where No-Bag Lines were backing up and security was
not letting those people enter thru the shorter Bag Line. A fail-safe for that is stuffing a plastic bag in your pocket and taking it out and putting your phone or whatever else in there so you could use the shorter Bag Line. This only happened for a few days though, probably won't be a concern again.