Improve docstring for AutoTapir (#68)

* Improve docstring for AutoTapir

* Bump patch

Author: willtebbutt

Project.toml

@@ -3,7 +3,7 @@ uuid = "47edcb42-4c32-4615-8424-f2b9edc5f35b"
 authors = [
     "Vaibhav Dixit <[email protected]>, Guillaume Dalle and contributors",
 ]
-version = "1.5.2"
+version = "1.5.3"
 
 [deps]
 ChainRulesCore = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"

src/dense.jl

@@ -287,7 +287,13 @@ Defined by [ADTypes.jl](https://github.com/SciML/ADTypes.jl).
 
 # Fields
 
-  - `safe_mode::Bool`: whether to run additional checks to catch errors early. On by default. Turn off to maximise performance if your code runs correctly.
+  - `safe_mode::Bool`: whether to run additional checks to catch errors early. While this is
+    on by default to ensure that users are aware of this option, you should generally turn
+    it off for actual use, as it has substantial performance implications.
+    If you encounter a problem with using Tapir (it fails to differentiate a function, or
+    something truly nasty like a segfault occurs), then you should try switching `safe_mode`
+    on and look at what happens. Often errors are caught earlier and the error messages are
+    more useful.
 """
 Base.@kwdef struct AutoTapir <: AbstractADType
     safe_mode::Bool = true