diff --git a/source/engine/mecanismViews/Allègement.js b/source/engine/mecanismViews/Allègement.js
index 6ba8e9597..93279b05d 100644
--- a/source/engine/mecanismViews/Allègement.js
+++ b/source/engine/mecanismViews/Allègement.js
@@ -1,60 +1,66 @@
 import React from 'react'
 import { Node } from './common'
 import { makeJsx } from '../evaluation'
-import { mapObjIndexed, values } from 'ramda'
+import { mapObjIndexed, map, values } from 'ramda'
 
-export default (nodeValue, explanation) => (
-	<div>
-		<Node
-			classes="mecanism allègement"
-			name="allègement"
-			value={nodeValue}
-			child={
-				<ul className="properties">
-					<li key="assiette">
-						<span className="key">assiette: </span>
-						<span className="value">{makeJsx(explanation.assiette)}</span>
-					</li>
-					{explanation.franchise && (
-						<li key="franchise">
-							<span className="key">franchise: </span>
-							<span className="value">{makeJsx(explanation.franchise)}</span>
-						</li>
-					)}
-					{explanation.décote && (
-						<li key="décote">
-							<span className="key">décote: </span>
-							<span className="value">
-								<ObjectView data={explanation.décote} />
-							</span>
-						</li>
-					)}
-					{explanation.abattement && (
-						<li key="abattement">
-							<span className="key">abattement: </span>
-							<span className="value">{makeJsx(explanation.abattement)}</span>
-						</li>
-					)}
-				</ul>
-			}
-		/>
-	</div>
-)
-
-let ObjectView = ({ data }) =>
-	console.log('data', data) || (
-		<ul className="properties">
-			{values(
-				mapObjIndexed(
-					(v, k) => (
-						<li key={k}>
-							{' '}
-							<span className="key">{k}: </span>
-							<span className="value">{makeJsx(v)}</span>
-						</li>
-					),
-					data
-				)
-			)}
-		</ul>
+export default function Allègement(nodeValue, rawExplanation) {
+	// properties with a nodeValue of 0 are not interesting to display
+	let explanation = map(
+		k => (k && k.nodeValue !== 0 ? k : null),
+		rawExplanation
 	)
+	return (
+		<div>
+			<Node
+				classes="mecanism allègement"
+				name="allègement"
+				value={nodeValue}
+				child={
+					<ul className="properties">
+						<li key="assiette">
+							<span className="key">assiette: </span>
+							<span className="value">{makeJsx(explanation.assiette)}</span>
+						</li>
+						{explanation.franchise && (
+							<li key="franchise">
+								<span className="key">franchise: </span>
+								<span className="value">{makeJsx(explanation.franchise)}</span>
+							</li>
+						)}
+						{explanation.décote && (
+							<li key="décote">
+								<span className="key">décote: </span>
+								<span className="value">
+									<ObjectView data={explanation.décote} />
+								</span>
+							</li>
+						)}
+						{explanation.abattement && (
+							<li key="abattement">
+								<span className="key">abattement: </span>
+								<span className="value">{makeJsx(explanation.abattement)}</span>
+							</li>
+						)}
+					</ul>
+				}
+			/>
+		</div>
+	)
+}
+
+let ObjectView = ({ data }) => (
+	<ul className="properties">
+		{values(
+			mapObjIndexed(
+				(v, k) => (
+					<li key={k}>
+						{' '}
+						<span className="key">{k}: </span>
+						<span className="value">{makeJsx(v)}</span>
+					</li>
+				),
+				data
+			)
+		)}
+	</ul>
+)
diff --git a/source/engine/mecanisms.js b/source/engine/mecanisms.js
index 44cd86661..db03fea4a 100644
--- a/source/engine/mecanisms.js
+++ b/source/engine/mecanisms.js
@@ -103,17 +103,14 @@ let decompose = (recurse, k, v) => {
 			}
 		/>
 	)
-	
+
 	let filter = situationGate => c =>
-               !situationGate('sys.filter') ||
-               !c.composante ||
-               (!c.composante['dû par'] ||
-			   c.composante['dû par'] == situationGate('sys.filter')) && 
-			   (!c.composante['impôt sur le revenu'] ||
-               c.composante['impôt sur le revenu'] == situationGate('sys.filter'))
-
-
-
+		!situationGate('sys.filter') ||
+		!c.composante ||
+		((!c.composante['dû par'] ||
+			c.composante['dû par'] == situationGate('sys.filter')) &&
+			(!c.composante['impôt sur le revenu'] ||
+				c.composante['impôt sur le revenu'] == situationGate('sys.filter')))
 
 	return {
 		explanation,
@@ -362,7 +359,11 @@ export let mecanismNumericalSwitch = (recurse, k, v) => {
 				evaluateNode(cache, situationGate, parsedRules, child),
 			explanation = map(evaluateOne, node.explanation),
 			nonFalsyTerms = filter(node => node.condValue !== false, explanation),
-			getFirst = o => pipe(head, prop(o))(nonFalsyTerms),
+			getFirst = o =>
+				pipe(
+					head,
+					prop(o)
+				)(nonFalsyTerms),
 			nodeValue =
 				// voilà le "numérique" dans le nom de ce mécanisme : il renvoie zéro si aucune condition n'est vérifiée
 				isEmpty(nonFalsyTerms)