Is there a logical explanation or rationale to get around supposed continuity errors between the series/FWWM/diary/etc. and view all of these various media and tie-ins as flowing together perfectly as one or did the writers/producers royally screw up?  I believe the former.  There are numerous examples of these supposed continuity glitches throughout the Twin Peaks universe.  Feel free to list examples of these supposed errors and how to debunk them.

continuity is always personal. some people don't think the grandson's name is pierre. some people don't even count the diary as "canon" i'm a pretty inclusive guy. i think cooper saw a blue dude, and that the history of the town as described in the town guide is as "true" as anything else. when things conflict, the movin' pictures are always the primary source, followed by the books, followed by everything else.

I know from my extremely cloudy memory a lot of the dates don't match up between the diary and the series/FWWM.  Alternate timeline?  Lodge time makes everything "off" just a bit?  Hmmm...

Oh, and of course how Cooper investigates in the diary and "Chester Desmond" in FWWM...

and WTF is the Passion Play referenced in the Access Guide?  I like to include everything as canon if I can even including the facts on the cards (BOB's birthdate says the beginning of time?!?!?) if I can logically give an explanation as to why.

A funny one is how the Pilot is supposed to be the day before Episode 1 yet since it was filmed a year earlier a lot of the main characters and their hairstyles change and/or get drastically longer or shorter in a 24 hour period.  I guess shorter could be explained by a haircut and longer by extensions or wigs LOL.

The magician did it.

The magician did it.

 Who is the magician?  The grandson?  Cooper?

When did Cooper become a magician?

When did Cooper become a magician?

 Some people have theorized online and elsewhere (articles,etc.?) that he may be the magician referred to in the Fire Walk with Me chant.  I can't remember the logic backing it up though. 

Could be a grand wizard without eyeholes in his hood maybe.
The fire is a burning cross.
Brand new theory.

Everything is canon.  There, I said it.  The show/film/diary/cooper book and tape/ cards/etc.  The show and the film are the core and everything else radiates outward from there.  I wish the 2 books were longer.  They are only about 180+ pages.   There is a page of phone numbers in the Access Guide and I will be calling the people one by one tonight.  Everything can be explained away.  When feeling lazy, just toss out the alternate timeline or Lodge time card.

Are the Nikes canon?

Are the Nikes canon?

 Of course, silly.  Since the Lodges can bend time, once they are released Ms. Tremond will travel forward, get them, and eventually be rocking them out next to Harold Smith and at Fat Trout Trailer Park.

be rocking them out next to Harold Smith

I am a lonely sole.

When she lived there, she used the shoes to swat flies that got in the apartment because of that pesky grandson and his creamed corn tricks that didn't go so well the first 764 times.  Harold could be heard next door pleasuring himself (with the help of apple butter)reading the diary of Laura aloud.

HAROLD TOLD DONNA HE HAD APPLE BUTTER.  WHAT WAS IT GOING TO BE SERVED ON?

HAROLD TOLD DONNA HE HAD APPLE BUTTER.  WHAT WAS IT GOING TO BE SERVED ON?

Her pert teen breasts...
 

Continuity obsessors drive me nuts. It's fiction, much of it written to baffle you. Everything goes.

HAROLD TOLD DONNA HE HAD APPLE BUTTER.  WHAT WAS IT GOING TO BE SERVED ON?

Her pert teen breasts...
 
 sometimes i just dont even know any more

I hate that you don't get to find out how Jerry actually did cook that leg of lamb, how he seasoned it, what temperature it was at, etc. It's a bit of a joke to leave that out really.

Also, Cooper is forever blowing that bloody whistle, but we never see what the Sheepdog is doing. Ridiculous really. I don't know what the writers were smoking.

I don't know what the writers were smoking.

Cheesy piggies. Suey!

Even the Georgia Coffee commercials are canon.

Oh, and of course how Cooper investigates in the diary and "Chester Desmond" in FWWM...

 That has been explained - Cooper was dreaming of being Chester Desmond in the first part of FWWM - There is no Chester Desmond.

Cooper's dream ends when you see Laura walking and the theme song is playing.

Oh, and of course how Cooper investigates in the diary and "Chester Desmond" in FWWM...

 That has been explained - Cooper was dreaming of being Chester Desmond in the first part of FWWM - There is no Chester Desmond.

Cooper's dream ends when you see Laura walking and the theme song is playing.

 That is why I put the name Chester Desmond in quotes.  :)

The magician did it.

 Who is the magician?  The grandson?  Cooper?
 In the poem, "The magician longs to see " refers to the Dugpas in the Black Lodge, all of whom are magicians. That's how they originally found the Black Lodge hundreds of years ago.Being magicians. That goes for BOB, Mike, the arm, the giant, the grandson, Mrs. Tremond etc. BUT NOT COOPER !!!!!!!!

The magician did it.

 Who is the magician?  The grandson?  Cooper?
 In the poem, "The magician longs to see " refers to the Dugpas in the Black Lodge, all of whom are magicians. That's how they originally found the Black Lodge hundreds of years ago.Being magicians. That goes for BOB, Mike, the arm, the giant, the grandson, Mrs. Tremond etc. BUT NOT COOPER !!!!!!!!
 Don't kill the messenger.  I never said Cooper was the magician.  I read a long theory on that either online or in a WIP (I'll have to find it).  So you think the Lodge spirits are dugpas?  Were they originally corporeal?