optimizations, unnecessary crap, undocumented ipc change

code/game/atoms.dm

@@ -505,9 +505,8 @@
 	return final_rgb
 
 /atom/proc/clean_blood()
-	if(islist(blood_DNA))
-		blood_DNA = null
-		return TRUE
+	. = blood_DNA? TRUE : FALSE
+	blood_dna = null
 
 /atom/proc/wash_cream()
 	return TRUE

code/game/machinery/suit_storage_unit.dm

@@ -266,7 +266,7 @@
 			for(var/atom/movable/AM in things_to_clear) //Scorches away blood and forensic evidence, although the SSU itself is unaffected
 				SEND_SIGNAL(AM, COMSIG_COMPONENT_CLEAN_ACT, CLEAN_STRONG)
 				AM.clean_blood()
-				AM.fingerprints = list()
+				AM.fingerprints = null
 				var/datum/component/radioactive/contamination = AM.GetComponent(/datum/component/radioactive)
 				if(contamination)
 					qdel(contamination)