Not quite but also, you know power trading markets have existed for a long time right and the lights stay on - probably a 99.9% uptime ;)

edit: Just re-read your comment I assumed you were implying high frequency trading as a bad thing - though it might have been to help non-energy people understand.

Well, you're not wrong! I understand power arbitrage is already a thing and for the most part it's OK. But once in a while you get situations like the crazy contracts in Texas a few years back. And I am a little concerned that if we create a large enough storage market controlled by a few big enough players, they could play financial games with a critical commodity, ie hoarding both generation and storage for peak resale value.

In both situations maybe there's an argument for market efficiencies and liquidity and such. But it scares me a little.

I am not a financial person (in the solar field, but not markets). I could totally be talking outta my ass!

There's always a risk of bad actors in any market. Hopefully we have learned and not forgotten the california energy crisis and Enron from the early 2000s. There are regulators who work on this though the market bad actors normally get caught a couple years after the fact. As long as the regulators keep catching them it seems likely that we won't have as many cheats.

The energy markets are significantly layered in power contracts that I would think it would be difficult for an energy storage provider to play that much of a position.

Well, there was this one energy trading company called Enron, and the power outages in California engineered to boost their profits. I'd say that some amount of weariness is justified in this case.