Comment adding context for group_by_epi_df_methods.R

Author: brookslogan

R/group_by_epi_df_methods.R

@@ -1,3 +1,9 @@
+# These methods (and maybe some others in methods-epi_df.R) are here to augment
+# `?dplyr_extending` implementations to get the correct behavior on grouped
+# `epi_df`s. It would be nice if there were a way to replace these with a
+# generic core that automatically fixed all misbehaving methods; see
+# brainstorming within Issue #223.
+
 #' @importFrom dplyr select
 #' @export
 select.epi_df <- function(.data, ...) {