Even though I have do not have a ton of SP sites under my belt, I have established, for myself, a good practice to follow when you are going to have many custom web parts on your SP site. I make a copy of the ItemStyle.xsl page and name it accordingly based on the project (e.g. "MyProject_ItemStyle.xsl").
At the bottom of the XSL sheet, right before the </xsl:stylesheet>, I put in the following code:
<xsl:template name="ShowVariables" match="Row[@Style='ShowVariables']" mode="itemstyle">
<xsl:for-each select="@*">
P:<xsl:value-of select="name()" /><br />
V:<xsl:value-of select="." /><br /><br />
</xsl:for-each>
</xsl:template>
What this will do is give you another drop-down option of displaying your web part in the web part toolbar in the UI. This comes in handy when you are trying to write custom code in your web part and need the "proper" name of a field opposed to the GUID (e.g. "General Information" would be "General_x0020_Information"). The "P" is the parameter in the case above and the "V" is the value being passed. This works for any web part that is referencing your new custom Item Style XSL file.
