That in your opinion it isn’t unbalanced, is not a justification to say it’s a good face value reading of the rule.
You might think it’s balanced but the Devs clearly didn’t want two spells to be cast with Action Surge whether by spellcasting or magic item. Which is why they specifically excluded that in the new version of Action Surge. They don’t want fighters to be better spell casters than single classed spell casters which seems right and sensible.
Right, but you’re not just casting two spells with action surge. You’re casting one spell with action surge and then trading your reaction and concentration for a
chance at casting a second spell, that can easily be disrupted.
Spending a reaction is the benefit you get from being able to affect something in the future that hasn’t happened yet. That’s the payoff. That’s what the reaction gets you. The same as for a move, or an attack, or a hide. One reaction in exchange for the option to wait and see. I cannot see why you think this also justifies giving additional benefits on top of that to exclude the clear and intentional restrictions of Action Surge for Magic Item use.
Additional benefits? What additional benefits? Having to use your concentration and your reaction are drawbacks, and that’s what makes this move fair, compared to casting the spell immediately with only your action.
This feels like an attempt to use semantics to try and get around those. Which the OP himself acknowledges was a workaround. I guess when there is any ambiguity, no matter how small, some folks want to push the boundaries. Always been that way, always will be. I’m just glad I don’t have those kinds of players at my tables and in my experience they seem pretty rare.
This isn’t about pushing boundaries, this seems to me to be pretty clearly both possible under the rules as written, and perfectly reasonable in terms of game balance. And I’m analyzing this from a perspective of a DM asking, would I allow a player to do this, not from the perspective of a player wanting to do it. Indeed, as a player I can’t really imagine wanting to do this, for the reasons I’ve already gone over of why it seems suboptimal to me.
As said earlier I think people search the internet when stuff like this comes. Both for table rulings but also exploits they can use on an unsuspecting DM and I think many of us want it to be clear that this is a controversial use and no DM should feel obliged to permit it in their games.
Sure. There are different possible ways to interpret these rules, and trying to argue that your DM’s interpretation is wrong is disruptive behavior as a player. Frankly, one shouldn’t do it even if the DM does happen to be wrong, because it’s ultimately their decision. If you take issue with a ruling the DM makes, you should discuss it with them privately, away from the table, not during game time. And if you do so, you should make your case, hea out theirs, and then either accept their final decision, or if it matters that much to you, leave the game. Lengthy debates like this are for DMs talking shop, not for players to try to make their DMs rule a certain way because the book says so (maybe, depending on your interpretation).