Basically the reading depends on if you're just straight up out to get the player for daring to use this spell.
There is that as well. The discussion between
@Maxperson and me focussed on another area entirely, which was the precision of the rules, their openness, and the link with the setting and the understanding as to how magic works.
But for sure, there can be a gamist discussion as well. On this one, honestly, while I know that caster are not the most frustrated of players in terms of possibilities, I have always found the lack of flexibility in spells to be a bit absurd. It might be a remain of my Ars Magica days, where spontaneous magic exists. It can be refined into formulaic, usually more powerful and les limited, and looking a bit like D&D. But D&D lacks spontaneous magic, and metamagic is really a poor substitute.
Anyway, my point is that I really like having spells which are more flexible, as a principle. And I also believe that the DM should be generous with the players' fun. And that might come from our long campaigns of Amber Diceless RPG, where the PCs are already incredibly powerful, but the game still says "and if they want more power, just give it to them".
I don't think that there is ANYTHING to be gained by imposing a restrictive version of spells, honestly. It will just frustrate the player and honestly, edge cases like that will happen once in a blue moon. As has been pointed out, it's not efficient anyway. So what's the point in letting the player out in the one instance where it would matter in a campaign ? He will feel good for it and, as a DM, you should be happy about that.
Of course, you should not let players abuse the system all the time with totally ridiculous reading anyway, there should be limits and it's up to the DM to control this, in particular so that fun is spread equitably for the players at the table. But are we really in that kind of case here ? Is it really an abuse ? Honestly...