diff --git a/cmdstanpy/model.py b/cmdstanpy/model.py
index c878d8ce..116e11b4 100644
--- a/cmdstanpy/model.py
+++ b/cmdstanpy/model.py
@@ -29,13 +29,7 @@
 import pandas as pd
 from tqdm.auto import tqdm
 
-from cmdstanpy import (
-    _CMDSTAN_REFRESH,
-    _CMDSTAN_SAMPLING,
-    _CMDSTAN_WARMUP,
-    _TMPDIR,
-    compilation,
-)
+from cmdstanpy import _CMDSTAN_SAMPLING, _CMDSTAN_WARMUP, _TMPDIR, compilation
 from cmdstanpy.cmdstan_args import (
     CmdStanArgs,
     GenerateQuantitiesArgs,
@@ -1069,9 +1063,6 @@ def sample(
                     iter_total += _CMDSTAN_SAMPLING
                 else:
                     iter_total += iter_sampling
-                if refresh is None:
-                    refresh = _CMDSTAN_REFRESH
-                iter_total = iter_total // refresh + 2
 
                 progress_hook = self._wrap_sampler_progress_hook(
                     chain_ids=chain_ids,
@@ -2138,13 +2129,12 @@ def _wrap_sampler_progress_hook(
         process, "Chain [id] Iteration" for multi-chain processing.
         For the latter, manage array of pbars, update accordingly.
         """
-        pat = re.compile(r'Chain \[(\d*)\] (Iteration.*)')
+        chain_pat = re.compile(r'(Chain \[(\d+)\] )?Iteration:\s+(\d+)')
         pbars: Dict[int, tqdm] = {
             chain_id: tqdm(
                 total=total,
-                bar_format="{desc} |{bar}| {elapsed} {postfix[0][value]}",
-                postfix=[{"value": "Status"}],
                 desc=f'chain {chain_id}',
+                postfix='(Warmup)',
                 colour='yellow',
             )
             for chain_id in chain_ids
@@ -2153,23 +2143,19 @@ def _wrap_sampler_progress_hook(
         def progress_hook(line: str, idx: int) -> None:
             if line == "Done":
                 for pbar in pbars.values():
-                    pbar.postfix[0]["value"] = 'Sampling completed'
+                    pbar.set_postfix_str('(Sampling completed)')
                     pbar.update(total - pbar.n)
                     pbar.close()
-            else:
-                match = pat.match(line)
-                if match:
-                    idx = int(match.group(1))
-                    mline = match.group(2).strip()
-                elif line.startswith("Iteration"):
-                    mline = line
-                    idx = chain_ids[idx]
-                else:
-                    return
-                if 'Sampling' in mline:
-                    pbars[idx].colour = 'blue'
-                pbars[idx].update(1)
-                pbars[idx].postfix[0]["value"] = mline
+            elif (match := chain_pat.match(line)) is not None:
+                idx = int(match.group(2) or chain_ids[idx])
+                current_iter = int(match.group(3))
+
+                pbar = pbars[idx]
+                if pbar.colour == 'yellow' and 'Sampling' in line:
+                    pbar.colour = 'blue'
+                    pbar.set_postfix_str('(Sampling)')
+
+                pbar.update(current_iter - pbar.n)
 
         return progress_hook
 
@@ -2225,8 +2211,7 @@ def diagnose(
             Gradients are evaluated in the unconstrained space.
         """
 
-        with temp_single_json(data) as _data, \
-                temp_single_json(inits) as _inits:
+        with temp_single_json(data) as _data, temp_single_json(inits) as _inits:
             cmd = [
                 str(self.exe_file),
                 "diagnose",