I’m feeling a bit torn myself. I understand the thinking behind the vanilla rules; it helps balance out some of the spellcasters’ power, especially at higher levels. But my understanding of balance in 5e is that it’s to balance the players against each other, to avoid having 1 or 2 players be so clearly better at so much that it naturally pulls the limelight away from the rest of the party and causes people to lose interest their own character.
I think totally unrestricted spellcasting carries the potential for imbalance, but doesn’t guarantee that outcome, and if I’m not making my spellcasters manage their resources then I’m doing something wrong. Something like Matt Mercer’s house rule “spells of 2nd level or lower” would also be a good compromise because it allows the utility of things like Misty Step, or for a Gish to summon a shadow blade etc.
What do y’all do at your tables, and why?
I feel like this is one of those rules that’s only really necessary if you have a player who cheeses it like that. If a player discovers it and uses it in moderation, well, that’s less likely to break things. If you have a player who builds their character to exploit it…
If you have a player who builds characters to exploit the system then that’s a player who needs a talking to, most likely.
I, personally, think this is a totally valid tactic, and wouldn’t be upset if a player used it in my game. One of the first things we go over in Session Zero, though, is that your characters, while unusual, are not unique. Any BBEG worth his stuff is capable of scrying on your tactics and hiring a hit squad that can copy or counter your tactics.
If a player started doing this repeatedly and trivialized many encounters, maybe the next group has his own sorcerer that can do that, or knows disintegrate, or can teleport the big stompy guy into the obvious spellcaster’s face. Cheese isn’t an arms race the players can win.