I hope this makes sense.
>2 different comment languages for one project dependent from the base class? It is nichtmare, i think.
..
PS: It is worst as I thinking. I can have 2 different comment languages in one class!!
/// <summary> Gets or sets a value indicating whether [hook mouse down]. </summary>
/// <value><c>true</c> if [hook mouse down]; otherwise, <c>false</c>.</value> public virtual bool HookMouseDown
...
/// <summary> Ruft den aktuellen Text in der <see cref="T:System.Windows.Forms.TextBox"/> ab oder legt diesen fest. /// </summary>
/// <value></value>/// <returns> Der im Steuerelement angezeigte Text. /// </returns>
public override string Text
...
Ps1:But comments itself is great.
Ps2: I think I understood why you did it. "It is better to copy comments from the parent class as create it new". For me it make sence to create 2 settings: Don't copy comments from system library, don't copy comments from parent class.