I'm with
@PfcAJ on this one. TBO makes 0 sense in OW, but even in a cave, if you're doing dives that big, just do a setup dive the day before and bring everything in ahead of time if it is impractical to carry with you. Sure it's an extra dive, but if you're doing stuff that big doing a setup dive to make sure that you take the time to ensure everything is where it is supposed to be isn't going to off you. On the way out you can grab what you can and start shuffling it close to the entrance if you can't bring it all out.
Things I can see TBO being used for.
Buddy bottles that are just adding extra conservatism but are outside of the amount of gas you SHOULD be able to bring out. I.e. we bring an extra AL80 of O2 in for the team, and we usually bring at least one extra AL80 just in case *mainly hypercapnia as I'm particularly sensitive to CO2 headaches*, but everyone has 1.5x-2x the gas they should need to get out.
The extra scooter is a team scooter but that is more for convenience as we all have gas enough to kick out so it's to make the deco obligation more tolerable.
Neither of those are necessary, just warm fuzzy conveniences that aren't really "bailout" options