Index: binaries/data/mods/public/globalscripts/Technologies.js
===================================================================
--- binaries/data/mods/public/globalscripts/Technologies.js
+++ binaries/data/mods/public/globalscripts/Technologies.js
@@ -19,6 +19,16 @@
 	if (!modifications.length)
 		return originalValue;
 
+	// From indicative profiling, splitting in two sub-functions or checking directly
+	// is about as efficient, but splitting makes it easier to report errors.
+	if (typeof originalValue === "string")
+		return GetTechModifiedProperty_string(modifications, classes, originalValue);
+	return GetTechModifiedProperty_numeric(modifications, classes, originalValue);
+}
+
+
+function GetTechModifiedProperty_numeric(modifications, classes, originalValue)
+{
 	let multiply = 1;
 	let add = 0;
 
@@ -28,18 +38,33 @@
 			continue;
 		if (modification.replace !== undefined)
 			return modification.replace;
-		if (modification.tokens !== undefined)
-			return HandleTokens(originalValue, modification.tokens);
-		if (modification.multiply)
+		else if (modification.multiply)
 			multiply *= modification.multiply;
 		else if (modification.add)
 			add += modification.add;
 		else
-			warn("GetTechModifiedProperty: modification format not recognised : " + uneval(modification));
+			warn("GetTechModifiedProperty: numeric modification format not recognised : " + uneval(modification));
 	}
 	return originalValue * multiply + add;
 }
 
+function GetTechModifiedProperty_string(modifications, classes, originalValue)
+{
+	for (let modification of modifications)
+	{
+		if (!DoesModificationApply(modification, classes))
+			continue;
+		if (modification.replace !== undefined)
+			return modification.replace;
+		else if (modification.tokens !== undefined)
+			return HandleTokens(originalValue, modification.tokens);
+		else
+			warn("GetTechModifiedProperty: string modification format not recognised : " + uneval(modification));
+	}
+	return originalValue;
+}
+
+
 /**
  * Returns whether the given modification applies to the entity containing the given class list
  */
Index: binaries/data/mods/public/globalscripts/tests/test_Technologies_effects.js
===================================================================
--- /dev/null
+++ binaries/data/mods/public/globalscripts/tests/test_Technologies_effects.js
@@ -0,0 +1,47 @@
+// This tests the GetTechModifiedProperty function.
+
+function test_numeric()
+{
+	let add = [{ "add": 10, "affects": "Unit" }];
+
+	let add_add = [{ "add": 10, "affects": "Unit" }, { "add": 5, "affects": "Unit" }];
+
+	let add_mul_add = [{ "add": 10, "affects": "Unit" }, { "multiply": 2, "affects": "Unit" }, { "add": 5, "affects": "Unit" }];
+
+	let add_replace = [{ "add": 10, "affects": "Unit" }, { "replace": 10, "affects": "Unit" }];
+
+	let replace_add = [{ "replace": 10, "affects": "Unit" }, { "add": 10, "affects": "Unit" }];
+
+	let replace_replace = [{ "replace": 10, "affects": "Unit" }, { "replace": 30, "affects": "Unit" }];
+
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(add, "Unit", 5), 15);
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(add_add, "Unit", 5), 20);
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(add_add, "Other", 5), 5);
+
+	// Technologies work by multiplying then adding all.
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(add_mul_add, "Unit", 5), 25);
+
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(add_replace, "Unit", 5), 10);
+
+	// Only the first replace is taken into account
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_replace, "Unit", 5), 10);
+}
+test_numeric();
+
+function test_non_numeric()
+{
+	let replace_nonnum = [{ "replace": "alpha", "affects": "Unit" }];
+
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_nonnum, "Unit", "beta"), "alpha");
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_nonnum, "Structure", "beta"), "beta");
+
+	let replace_tokens = [{ "tokens": "-beta alpha gamma -delta", "affects": "Unit" }];
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_tokens, "Unit", "beta"), "alpha gamma");
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_tokens, "Structure", "beta"), "beta");
+
+	let replace_tokens_2 = [{ "tokens": "beta>gamma -delta", "affects": "Unit" }];
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_tokens_2, "Unit", "beta"), "gamma");
+	TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_tokens_2, "Structure", "beta"), "beta");
+}
+
+test_non_numeric();
Index: binaries/data/mods/public/globalscripts/tests/test_Technologies_reqs.js
===================================================================
--- binaries/data/mods/public/globalscripts/tests/test_Technologies_reqs.js
+++ binaries/data/mods/public/globalscripts/tests/test_Technologies_reqs.js
@@ -1,5 +1,3 @@
-// TODO: Move this to a folder of tests for GlobalScripts (once one is created)
-
 // No requirements set in template
 let template = {};
 TS_ASSERT_UNEVAL_EQUALS(DeriveTechnologyRequirements(template, "athen"), []);
Index: binaries/data/mods/public/simulation/components/tests/test_Technologies_effects.js
===================================================================
--- binaries/data/mods/public/simulation/components/tests/test_Technologies_effects.js
+++ /dev/null
@@ -1,30 +0,0 @@
-// TODO: Move this to a folder of tests for GlobalScripts (once one is created)
-
-// This tests the GetTechModifiedProperty function.
-let add = [{ "add": 10, "affects": "Unit" }];
-
-let add_add = [{ "add": 10, "affects": "Unit" }, { "add": 5, "affects": "Unit" }];
-
-let add_mul_add = [{ "add": 10, "affects": "Unit" }, { "multiply": 2, "affects": "Unit" }, { "add": 5, "affects": "Unit" }];
-
-let add_replace = [{ "add": 10, "affects": "Unit" }, { "replace": 10, "affects": "Unit" }];
-
-let replace_add = [{ "replace": 10, "affects": "Unit" }, { "add": 10, "affects": "Unit" }];
-
-let replace_replace = [{ "replace": 10, "affects": "Unit" }, { "replace": 30, "affects": "Unit" }];
-
-let replace_nonnum = [{ "replace": "alpha", "affects": "Unit" }];
-
-TS_ASSERT_EQUALS(GetTechModifiedProperty(add, "Unit", 5), 15);
-TS_ASSERT_EQUALS(GetTechModifiedProperty(add_add, "Unit", 5), 20);
-TS_ASSERT_EQUALS(GetTechModifiedProperty(add_add, "Other", 5), 5);
-
-// Technologies work by multiplying then adding all.
-TS_ASSERT_EQUALS(GetTechModifiedProperty(add_mul_add, "Unit", 5), 25);
-
-TS_ASSERT_EQUALS(GetTechModifiedProperty(add_replace, "Unit", 5), 10);
-
-// Only the first replace is taken into account
-TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_replace, "Unit", 5), 10);
-
-TS_ASSERT_EQUALS(GetTechModifiedProperty(replace_nonnum, "Unit", "beta"), "alpha");