Remvoing age-related caveat from Kernel loop tutorial

Author: erikvansebille

docs/examples_v3/tutorial_kernelloop.ipynb

@@ -240,24 +240,16 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Caveats"
+    "## Caveat: Avoid updating particle locations directly in Kernels"
    ]
   },
   {
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "There are a few important considerations to take into account when writing Kernels\n",
-    "\n",
-    "### 1. Avoid updating particle locations directly in Kernels\n",
     "It is better not to update `particle.lon` directly in a Kernel, as it can interfere with the loop above. Assigning a value to `particle.lon` in a Kernel will throw a warning. \n",
     "\n",
-    "Instead, update the local variable `particle.dlon`.\n",
-    "\n",
-    "### 2. Be careful with updating particle variables that do not depend on Fields.\n",
-    "While assigning the interpolated value of a `Field` to a Particle goes well in the loop above, this is not necessarily so for assigning other attributes. For example, a line like `particle.age += particle.dt` is executed directly so may result in the age being `dt` at `time = 0` in the output file. \n",
-    "\n",
-    "A workaround is to either initialise the age to `-dt`, or to increase the `age` only when `particle.time > 0` (using an `np.where` statement)."
+    "Instead, update the local variable `particle.dlon`."
    ]
   },
   {