diff --git a/Svelto.Common b/Svelto.Common
index 4f7d4d9..70c3fa3 160000
--- a/Svelto.Common
+++ b/Svelto.Common
@@ -1 +1 @@
-Subproject commit 4f7d4d96407f3ce390a23b930ba235a2447729ec
+Subproject commit 70c3fa30662f89cd1b023802f114dd917e156d2e
diff --git a/Svelto.ECS/DataStructures/TypeSafeDictionary.cs b/Svelto.ECS/DataStructures/TypeSafeDictionary.cs
index 5266477..9d33194 100644
--- a/Svelto.ECS/DataStructures/TypeSafeDictionary.cs
+++ b/Svelto.ECS/DataStructures/TypeSafeDictionary.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using Svelto.DataStructures;
 using Svelto.DataStructures.Experimental;
@@ -32,6 +32,7 @@ namespace Svelto.ECS.Internal
         bool Remove(int idGid);
         
         int Count { get; }
+        void Trim();
     }
 
     class TypeSafeDictionary<TValue> : FasterDictionary<int, TValue>, ITypeSafeDictionary where TValue : IEntityStruct
diff --git a/Svelto.ECS/Dispatcher/DispatchOnChange.cs b/Svelto.ECS/Dispatcher/DispatchOnChange.cs
index b6ddb5f..68a4ad1 100644
--- a/Svelto.ECS/Dispatcher/DispatchOnChange.cs
+++ b/Svelto.ECS/Dispatcher/DispatchOnChange.cs
@@ -7,9 +7,6 @@ namespace Svelto.ECS
         public DispatchOnChange(int senderID) : base(senderID)
         { }
         
-        public DispatchOnChange(EGID senderID) : base(senderID)
-        { }
-
         public DispatchOnChange() {}
 
         public new T value
diff --git a/Svelto.ECS/Dispatcher/DispatchOnSet.cs b/Svelto.ECS/Dispatcher/DispatchOnSet.cs
index fddaba8..bd38c07 100644
--- a/Svelto.ECS/Dispatcher/DispatchOnSet.cs
+++ b/Svelto.ECS/Dispatcher/DispatchOnSet.cs
@@ -4,22 +4,17 @@ namespace Svelto.ECS
 {
     public class DispatchOnSet<T> where T:struct
     {
-        public DispatchOnSet(int senderID):this()
+        public DispatchOnSet(int senderID)
         {
-            _senderID    = new EGID(senderID, ExclusiveGroup.StandardEntitiesGroup);
+            _senderID    = senderID;
+            _subscribers = new WeakEvent<int, T>();
         }
-        
-        public DispatchOnSet(EGID senderID):this()
-        {
-            _senderID = senderID;
-        }
-        
+
         public DispatchOnSet()
-        {
-            _senderID    = new EGID();
-            _subscribers = new WeakEvent<EGID, T>();
+        {      
+            _subscribers = new WeakEvent<int, T>();
         }
-
+        
         public T value
         {
             set
@@ -35,19 +30,19 @@ namespace Svelto.ECS
             }
         }
         
-        public void NotifyOnValueSet(System.Action<EGID, T> action)
+        public void NotifyOnValueSet(System.Action<int, T> action)
         {
             _subscribers += action;
         }
 
-        public void StopNotify(System.Action<EGID, T> action)
+        public void StopNotify(System.Action<int, T> action)
         {
             _subscribers -= action;
         }
 
         protected T      _value;
-        readonly EGID _senderID;
+        readonly int _senderID;
 
-        WeakEvent<EGID, T> _subscribers;
+        WeakEvent<int, T> _subscribers;
     }
 }
diff --git a/Svelto.ECS/EGID.cs b/Svelto.ECS/EGID.cs
index 7e21114..e4e5612 100644
--- a/Svelto.ECS/EGID.cs
+++ b/Svelto.ECS/EGID.cs
@@ -1,5 +1,3 @@
-using Svelto.ECS.Internal;
-
 namespace Svelto.ECS
 {
     public struct EGID
diff --git a/Svelto.ECS/EnginesRoot.Entities.cs b/Svelto.ECS/EnginesRoot.Entities.cs
index a079afc..8ed5a3b 100644
--- a/Svelto.ECS/EnginesRoot.Entities.cs
+++ b/Svelto.ECS/EnginesRoot.Entities.cs
@@ -150,7 +150,9 @@ namespace Svelto.ECS
             {
                 _groupedGroups[entityType].Remove(toGroupID);
 
-                fromGroup.Remove(entityType);
+                //it's probably better to not remove this, but the dictionary should be trimmed?
+                //fromGroup.Remove(entityType);
+                fromTypeSafeDictionary.Trim();
             }
             
             //it doesn't eliminate the fromGroup itself on purpose
diff --git a/Svelto.ECS/EnginesRoot.Submission.cs b/Svelto.ECS/EnginesRoot.Submission.cs
index 94d8b43..c9f94bc 100644
--- a/Svelto.ECS/EnginesRoot.Submission.cs
+++ b/Svelto.ECS/EnginesRoot.Submission.cs
@@ -90,7 +90,7 @@ namespace Svelto.ECS
         //one datastructure rule them all:
         //split by group
         //split by type per group. It's possible to get all the entities of a give type T per group thanks 
-        //to the FasterDictionary capabilitiies OR it's possible to get a specific entityView indexed by
+        //to the FasterDictionary capabilities OR it's possible to get a specific entityView indexed by
         //ID. This ID doesn't need to be the EGID, it can be just the entityID
         
         readonly Dictionary<int, Dictionary<Type, ITypeSafeDictionary>>       _groupEntityDB;