Quite frankly I never understood why it was included on the album. Especially since the actual song 'House of the Holy' was not included on the album. I agree that it was a nod to funk, and it's about as good a tribute to funk that a band of English white guys can pull off.
Bonzo started just playing a beat from James Brown, and Jimmy joined in. It just developed from there.
But that's not to say it is a failure.
As someone fascinated by music, this song thrills me on many levels. Bonham's off-time drum shuffle is infectious, I love listening to JPJ's bass and keyboard work, and I love how Robert's vocals (on first listen) sound like they're cut from a completely different song, but then you hear the the vocal mesh together with the music, and it is wonderful to hear.
I could listen to that song anytime.
I like the live versions of the song a bit better, because they can jam a bit while playing it.
But like all of the early 1970's 'Classic Rock' bands, Zep was influenced heavily by the 1960's Motown and Funk bands, like James Brown. So this song is an homage to James Brown.
But the song does not play so well with Zep's original demographic group - people who were teens in the 1970's.
Please note, this is when Jonesy started being more prominent with his keyboard. Yes, it was getting more traction in IV, but Jimmy let him start to shine in Houses Of the Holy.
I enjoy the groove of it, but I just don't think it fits the rest of the album, which is actually my favorite zeppelin album.