D&D 5E When is it OK to let a player substitute one skill for another?

[Don Durito]

I like skills. I really don't want a game where the only crunch is for fighting.

I was part of the playtest and sentiment for skills was strong. I find the current mechanics function better than I expected

There isn't any crunch to be removed and what crunch there is would just naturally be moved. (You would still be able to add proficiency to grappling for example, it just wouldn't be Athletics).

 

[Don Durito]

Not sure I follow. If you need to lift a heavy portcullis, it's just a strength check. Need to keep that heavy portcullis open long enough for the party to get through, it's a con check. Need to figure out the mechanism to keep the portcullis open might be an intelligence check because although the mechanism is clearly visible and there are instructions, the instructions were written by the same people that do the instructions for Ikea*.

Does that answer the question?

*Although admittedly that may be an investigation check, or a wisdom saving throw vs insanity.

I let players add Athletics to that. I know the rules say Athletics doesn't support feats of raw strength, but since there are no other available skills and the game is intended to scale...

 

[Charlaquin]

I let players add Athletics to that. I know the rules say Athletics doesn't support feats of raw strength, but since there are no other available skills and the game is intended to scale...

Notably a lot of example Strength DCs are like a difficulty tier lower than one might expect (e.g. breaking out of manacles being DC 10, or “easy”), probably for this reason. I do allow Athletics to be added to most strength checks though.

 

[Vael]

I generally don't swap skills, but I will swap abilities. For example, I have a high-Int Mastermind Rogue. I've allowed him to use Intelligence in place of Charisma in Intimidation checks, because he's browbeating a guy with the force of his mind, like how Sherlock Holmes does.

 

[Fauchard1520]

I generally don't swap skills, but I will swap abilities. For example, I have a high-Int Mastermind Rogue. I've allowed him to use Intelligence in place of Charisma in Intimidation checks, because he's browbeating a guy with the force of his mind, like how Sherlock Holmes does.

I dig that a lot actually. I feel like players usually want to roll their "best skill" from a pure numbers standpoint. This solution lets them get a bit of a mechanical boost while still describing the actual situation.

For example, I like substituting Int (Intimidation) a lot more than letting a player roll Int (Investigtion) in this example. The player might argue that, "I'm using my knowledge of this guy's past to intimidate him, which involves investigation," but that feels like a weak sauce substitution for the standard Cha (Intimidate) check to me. With Int (Intimidation) you can accommodate both sides of the argument and respect the unique way the player is trying to conduct the check.