add sentence to fit_tmb docs

R/fit_tmb.R

@@ -26,7 +26,9 @@
 #'        and therefore this option can be used to achieve an arbitrarily low final gradient
 #'        given sufficient time for well-behaved models.  However, this option will also
 #'        perform strangely or have unexpected consequences for poorly-behaved models, e.g.,
-#'        when fixed effects are at upper or lower bounds.
+#'        when fixed effects are at upper or lower bounds. There is no need to increase the value
+#'        of newtonsteps if the model appears to be converged (i.e., has low final_gradient and none of
+#'        the standard errors are NA values)
 #' @param n sample sizes (if \code{n!=Inf} then \code{n} is used to calculate BIC and AICc)
 #' @param getHessian return Hessian for usage in later code
 #' @param quiet Boolean whether to print additional messages results to terminal