system
Given the following post, respond as if you're commenting on Reddit:
human
[Supernatural] Why aren't the boys better actors?

Kind of an obscure question, but: in the Season 6 episode *The French Mistake*, there's a gag where Sam and Dean have to pretend to be actors and fail miserably. They act woodenly, constantly forget lines, end up reading all their lines off pieces of paper and ruining every single take that day.

These are guys who's day job involves pretending to be other people (FBI agents etc), and memorizing complex incantations (Dean actually re-writes a ritual from memory he only saw once in the same episode!) Shouldn't their skills be extremely transferable to a  TV set?
gpt
It depends on the nature of the set.

Incantations are recited, not delivered; you don't normally have to act while giving them. Meanwhile, most of their "acting" - their impersonation - is done on an improvisational level, constantly adapting to the reactions of the people they're trying to fool.

Forcing them to stick to a script stifled their improvisational skills, leaving them off balance and unable to properly inhabit their characters. Hence, wooden line readings and general uncertainty.

They probably should have done better at learning their lines, but there were two big differences from memorising incantations - firstly, most incantations are written to be chanted, giving them a natural rhythm and tendency towards repetition, both of which help when trying to remember then; and secondly, when they're learning incantations they know that it's basically life or death, adding focus to their efforts, while it is quite simply impossible for them to take the script that seriously, leading to them unconsciously half-assing it.