Filter IN on "array" in SQL-Server

MultiFilter.sql

DECLARE @SO_UIDs varchar(MAX); 

SET @SO_UIDs = 'F2808163-C192-4860-9C32-2514F880F123,DDCC699D-B525-4DA3-A558-3BE87AA8923A,043AB989-AA6C-4621-AF26-44C9D537483B,DB14B864-6F96-41B9-BD22-51EAEABC46B9,60DF0FF4-AC1E-4526-8511-653F07CB19C3'; 
-- SET @SO_UIDs = '81f82b66-5cc1-4985-869f-cade014fb4a4'; 
-- SET @SO_UIDs = NULL 
-- SET @SO_UIDs = '00000000-0000-0000-0000-000000000000'; 


DECLARE @tXML xml; 
SET @tXML = CAST(('<e>' + REPLACE(NULLIF(@SO_UIDs, '00000000-0000-0000-0000-000000000000'), ',', '</e><e>') + '</e>') AS xml); 
-- PRINT CAST(@tXML  AS nvarchar(4000))


DECLARE @numFilterItems int;
SET @numFilterItems = (SELECT COUNT(nodeList.ele.value('.', 'varchar(36)')) FROM @tXML.nodes('e') AS nodeList(ele));
-- PRINT @numFilterItems 


SELECT 
	 T_AP_Standort.SO_UID 
	,T_AP_Standort.SO_Nr 
	,T_AP_Standort.SO_Bezeichnung 
FROM T_AP_Standort 
WHERE (1=1) 
AND 
( 
	T_AP_Standort.SO_UID IN 
	( 
		SELECT nodeList.ele.value('.', 'varchar(36)') FROM @tXML.nodes('e') AS nodeList(ele) 
	) 
	OR @numFilterItems = 0 
)