Hmmm.... I'll look at it some more and post back. However, very briefly this is what happened... (I looked)
A long time ago, I built a set of "filtered" View Schemes that works just like SmartLists. This allows me to use the Panes/Tiles/whatever with a Smartlist-like list. I now want to take these and make duplicates of them in actual Smartlists, but modify them to make them much smaller, and use them to sync to my iPods.
So, for example, I have one called "Mostly Classic Things" (I give them cute names that make them cheesy but intuitive to know what they are). That view has these filters, created using the normal "Edit Search" dialog functionality:
Rules:
[Media Type] is Audio
[Genre] is Bluegrass;Classic Rock;Country;Folk;Oldies;Psychedelic Rock;Rock
[Artist] is not (huge list of 30 artists or so that fall into those genres, but which I don't want included in this list because they aren't "classic")
Modifiers:
Mix: 2160,10%,{[Genre]=[Bluegrass]},20%,{[Genre]=[Classic Rock]},10%,{[Genre]=[Country]},17%,{[Genre]=[Folk]},17%,{[Genre]=[Oldies]},17%,{[Genre]=[Psychedelic Rock]},9%,{[Genre]=[Rock]}
Sort By: Artist, Album, Disc #, Track #, Name
Again, that was built a long while ago, but was built using the then-available Search Editor thing.
Now, when I open that View's Import/Export dialog and hit the Copy button (or use Control-C or whatever), this is what I get:
[Media Type]=[Audio] [Genre]=[Bluegrass],[Classic Rock],[Country],[Folk],[Oldies],[Psychedelic Rock],[Rock] -[Artist]=[Adams, Brian],[Aerosmith],[air],[Anastasio, Trey],[Bad Finger],[Be Good Tanyas, the],[Belle and Sebastian],[person and Animal],[Bright Eyes],[Bush, Sam],[Coldplay],[Crow, Cheryl],[Crow, Sheryl],[Crystal Method, the],[Danzig],[Dar Williams],[Deep Purple],[Difranco, Ani],[Dixie Chicks],[Drake, Nick],[Etheridge, Melissa],[Evanescence],[Finn, Neil],[Frankie Goes To Hollywood],[Garcia, Jerry & David Grisman],[Grey, David],[Harper, Ben],[Hawkwind],[Hay, Colin],[Indigo Girls],[Interpol],[Jackson 5],[Jet],[Jett, Joan],[Jones, Laurie],[Kravitz, Lenny],[Kreviazuk, Chantal],[Legendary Pink Dots],[Living Color],[Mazzy Star],[McKee, Maria],[McKenzie, Scott],[Nickel Creek],[Nugent, Ted],[Oysterhead],[Pinback],[Queen],[radiohead],[Rusted Root],[Sage, Rachael],[Scorpions],[Shinedown],[Sinatra, Frank],[Springsteen, Bruce],[Squier, Billy],[Stanley, Ralph],[String Cheese Incident],[Styx],[Tangerine Dream],[Tegan and Sara],[The Warlocks],[Thile, Chris],[Tom & Lance],[Tom Waits],[Twain, Shania],[Tyminski, Dan],[Ugly Kid Joe],[Unknown],[Urge Overkill],[Various Artists],[Velvet Revolver],[War],[Ween],[Widespread Panic],[ZZ Top] ~mix=2160,10%,{[Genre]=[Bluegrass]},20%,{[Genre]=[Classic Rock]},10%,{[Genre]=[Country]},17%,{[Genre]=[Folk]},17%,{[Genre]=[Oldies]},17%,{[Genre]=[Psychedelic Rock]},9%,{[Genre]=[Rock]} ~sort=[Artist],[Album],[Disc #],[Track #],[Name]
However, what I actually SEE in the editor is only this (and I can't scroll and see more of it, that's all that is there):
[Media Type]=[Audio] [Genre]=[Bluegrass],[Classic Rock],[Country],[Folk],[Oldies],[Psychedelic Rock],[Rock] -[Artist]=[Adams, Brian],[Aerosmith],[air],[Anastasio, Trey],[Bad Finger],[Be Good Tanyas, the],[Belle and Sebastian],[person and Animal],[Bright Eyes],[Bush, Sam],[Coldplay],[Crow, Cheryl],[Crow, Sheryl],[Crystal Method, the],[Danzig],[Dar Williams],[Deep Purple],[Difranco, Ani],[Dixie Chicks],[Drake, Nick],[Etheridge, Melissa],[Evanescence],[Finn, Neil],[Frankie Goes To Hollywood],[Garcia, Jerry & David Grisman],[Grey, David],[Harper, Ben],[Hawkwind],[Hay, Colin],[Indigo Girls],[Interpol],[Jackson 5],[Jet],[Jett, Joan],[Jones, Laurie],[Kravitz, Lenny],[Kreviazuk, Chantal],[Legendary Pink Dots],[Living Color],[Mazzy Star],[McKee, Maria],[McKenzie, Scott],[Nickel Creek],[Nugent,
And, worse, even though the full search string DOES get copied to my clipboard, I can't paste it into the Import/Export dialog box of the new Smartlist, because it won't paste in. It is too long and it gives me a "invalid entry" system beep.
So, while the text string stored by the Application doesn't appear to be length limited (or if it is, the limit is much longer), the actual textbox entry field IS.