Simplify p tags?

what do we do about something like this complex nested <p>.

     <p>
          <span style="font-family: Palatino; font-size: 18; font-size: 18">Max Weber’s famous metaphor in </span>
         <span style="font-family: Palatino; font-size: 18; font-size: 18">
            <i>The Protestant Ethic</i>
         </span>
         <span style="font-family: Palatino; font-size: 18; font-size: 18"> of religion striding into the marketplace of worldly affairs and slamming the monastery door behind it becomes further transformed in modern society with religion placed very much in the consumer marketplace alongside other meaning complexes. </span>
      </p>

Is it safe to assume any span beneath a <p> is going to be either an inline style (ie. not a block style like a heading) and so if it contains a <span> with only font size and family information then this should be interpreted as extraneous? Alternatively, is it possible using xsl greps to identify that if sequential spans contain the same information then they should all just be contained within one span?

If, however, it contained another element (eg another nested <p> like below) then it is another kind of problem and should be left alone

      <p>
         <span style="font-family: Palatino; font-size: 20">The other great idea that the world wants from us today…is the eternal grand idea of the spiritual oneness of the whole universe…This is the dictate of Indian philosophy. This oneness is the rationale of all ethics and all spirituality. Europe wants it today just as much as our downtrodden masses do, and this great principle is even now unconsciously forming the basis of all the latest political and social aspirations that are coming up in England, in Germany, in France and in America.</span>
         <span style="font-family: Palatino; font-size: 20">
            <div class="endnote_fetched">
               <p class="EndnoteText">
                  <span style="font-size: 20; font-size: 20">
                     <span class="EndnoteReference"/>
                  </span>
                  <span style="font-size: 20; font-size: 20"> Vivekananda,</span>
                  <span style="font-size: 20; font-size: 20"> </span>
                  <span style="font-size: 20; font-size: 20">
                     <i>The Complete Works of Swami Vivekananda,</i>
                  </span>
                  <span style="font-size: 20; font-size: 20"> vol.3 (Calcutta: Advaita Ashram, 1983), </span>
                  <span style="font-size: 20; font-size: 20">p.189</span>
                  <span style="font-size: 20; font-size: 20">.</span>
               </p>
            </div>
         </span>
      </p>