diff --git a/README.md b/README.md
index e2be61f..624dc81 100644
--- a/README.md
+++ b/README.md
@@ -128,6 +128,11 @@ over you, so you can see when you can open without pulling aggro: `GO +4210` (gr
   threshold; a typical raid burst over 3 s is a few thousand threat, Execute crits can exceed 10000, so
   raise it to match your own burst); a *Threat* switch per list row (on for players, off for pets, totems,
   mobs and hostile players).
+- **Set the required buffer yourself.** AnySCT does not work it out for you: how much threat you can put out
+  in one burst depends on your class, spec, gear and buffs (an enhancement shaman's Windfury triple crit, a
+  warrior's Execute crit), and it changes as your gear improves. The default of 1500 suits a fresh level 60
+  or a levelling character. Watch how far your own biggest burst moves the number and set the slider at
+  least that high; GO only means "the tank's lead is bigger than the buffer you chose".
 - **Experimental:** the packet format is taken from the TWThreat addon and has not been confirmed on every
   server build. If it does not work for you, switch on *Record threat trace* (Placement tab, Debug) and
   send `<WoW>\imports\anysct_threat.txt` with your bug report (needs SuperWoW). The trace is off by default