diff --git a/validation/src/check.rs b/validation/src/check.rs
index 41fb341..7c2b70d 100644
--- a/validation/src/check.rs
+++ b/validation/src/check.rs
@@ -182,7 +182,7 @@ pub struct DuplicateCheck<ID>(Result<(),DuplicateCheckContext<ID>>);
 impl<ID> DuplicateCheckContext<ID>{
 	fn check(self)->DuplicateCheck<ID>{
 		let Self(mut set)=self;
-		// drop correct entries
+		// remove correct entries
 		set.retain(|_,&mut c|c!=1);
 		// if any entries remain, they are incorrect
 		if set.is_empty(){
@@ -195,33 +195,33 @@ impl<ID> DuplicateCheckContext<ID>{
 
 // check that there is at least one
 pub struct AtLeastOneMatchingAndNoExtraCheckContext<ID>{
-	set:HashMap<ID,u64>,
+	extra:HashMap<ID,u64>,
 	missing:HashSet<ID>,
 }
 pub struct AtLeastOneMatchingAndNoExtraCheck<ID>(Result<(),AtLeastOneMatchingAndNoExtraCheckContext<ID>>);
 impl<ID> AtLeastOneMatchingAndNoExtraCheckContext<ID>{
-	fn new(set:HashMap<ID,u64>)->Self{
+	fn new(initial_set:HashMap<ID,u64>)->Self{
 		Self{
-			set,
+			extra:initial_set,
 			missing:HashSet::new(),
 		}
 	}
 }
 impl<ID:Copy+Eq+std::hash::Hash> AtLeastOneMatchingAndNoExtraCheckContext<ID>{
 	fn check<T>(self,reference_set:&HashMap<ID,T>)->AtLeastOneMatchingAndNoExtraCheck<ID>{
-		let Self{mut set,mut missing}=self;
-		// drop correct entries
+		let Self{mut extra,mut missing}=self;
+		// remove correct entries
 		for (id,_) in reference_set{
-			if !set.remove(id).is_some(){
+			if extra.remove(id).is_none(){
 				// the set did not contain a required item.  This is a fail
 				missing.insert(*id);
 			}
 		}
 		// if any entries remain, they are incorrect
-		if set.is_empty()&&missing.is_empty(){
+		if extra.is_empty()&&missing.is_empty(){
 			AtLeastOneMatchingAndNoExtraCheck(Ok(()))
 		}else{
-			AtLeastOneMatchingAndNoExtraCheck(Err(Self{set,missing}))
+			AtLeastOneMatchingAndNoExtraCheck(Err(Self{extra,missing}))
 		}
 	}
 }
@@ -264,11 +264,10 @@ impl<'a> ModelInfo<'a>{
 			if display_name.is_empty(){
 				StringEmptyCheck(Err(StringEmpty))
 			}else{
-				let display_name=StringCheckContext{
+				StringEmptyCheck(Ok(StringCheckContext{
 					observed:display_name,
 					expected:Cow::Owned(display_name.to_title_case()),
-				}.check(display_name);
-				StringEmptyCheck(Ok(display_name))
+				}.check(display_name)))
 			}
 		});
 
@@ -299,7 +298,8 @@ impl<'a> ModelInfo<'a>{
 		};
 
 		// check that at least one end zone exists for each start zone.
-		let mode_finish_counts=AtLeastOneMatchingAndNoExtraCheckContext::new(self.counts.mode_finish_counts).check(&self.counts.mode_start_counts);
+		let mode_finish_counts=AtLeastOneMatchingAndNoExtraCheckContext::new(self.counts.mode_finish_counts)
+			.check(&self.counts.mode_start_counts);
 
 		// there must be exactly one start zone for every mode in the map.
 		let mode_start_counts=DuplicateCheckContext(self.counts.mode_start_counts).check();