diff --git a/src/field/cosets.rs b/src/field/cosets.rs
index 4ad9ba38..62be67dc 100644
--- a/src/field/cosets.rs
+++ b/src/field/cosets.rs
@@ -31,8 +31,6 @@ mod tests {
 
     #[test]
     fn distinct_cosets() {
-        // TODO: Switch to a smaller test field so that collision rejection is likely to occur.
-
         type F = GoldilocksField;
         const SUBGROUP_BITS: usize = 5;
         const NUM_SHIFTS: usize = 50;
diff --git a/src/gadgets/arithmetic.rs b/src/gadgets/arithmetic.rs
index 0931cc88..3d54bdc3 100644
--- a/src/gadgets/arithmetic.rs
+++ b/src/gadgets/arithmetic.rs
@@ -184,13 +184,8 @@ impl<F: RichField + Extendable<D>, const D: usize> CircuitBuilder<F, D> {
     }
 
     /// Add `n` `Target`s.
-    // TODO: Can be made `D` times more efficient by using all wires of an `ArithmeticExtensionGate`.
     pub fn add_many(&mut self, terms: &[Target]) -> Target {
-        let terms_ext = terms
-            .iter()
-            .map(|&t| self.convert_to_ext(t))
-            .collect::<Vec<_>>();
-        self.add_many_extension(&terms_ext).to_target_array()[0]
+        terms.iter().fold(self.zero(), |acc, &t| self.add(acc, t))
     }
 
     /// Computes `x - y`.
diff --git a/src/plonk/prover.rs b/src/plonk/prover.rs
index 4f281f06..94c2fa29 100644
--- a/src/plonk/prover.rs
+++ b/src/plonk/prover.rs
@@ -146,7 +146,6 @@ pub(crate) fn prove<F: RichField + Extendable<D>, const D: usize>(
             .into_par_iter()
             .flat_map(|mut quotient_poly| {
                 quotient_poly.trim();
-                // TODO: Return Result instead of panicking.
                 quotient_poly.pad(quotient_degree).expect(
                     "Quotient has failed, the vanishing polynomial is not divisible by `Z_H",
                 );