What does "traditional" really mean?

Synonyms from Roget's Thesaurus include: 

Old, legendary, unwritten, handed down, customary, conventional, understood, admitted, recognized, acknowledged, received, time-honored, immemorial, long-standing, established, fixed, inveterate, rooted, historical, legendary, chronological, biographical, conventional, customary, popular, formal, stipulated, established, fixed, accepted, recognized, acknowledged, approved, correct, right, proper, according to use or custom.

This breadth of meaning allows this word to mean all kinds of things to different people.  

To wit - 

• I was once asked to play a "traditional, Scottish, 1820s, midwest fur trader's wedding".  In this usage, the intention was to be historically accurate to what might have been done at the time.
• I've seen the authorship of many tunes as listed as "traditional". This happens frequently when people don't know who wrote the tune. (Note: Most pipers have seen "Scotland the Brave" listed in this way.  From what I can learn, this tune was an older pipe melody, but I can't find the name of it.  The lyric we all know was modified from an earlier lyric by Cliff Hanley in 1951.)
• Questions such as "Do you wear the traditional outfit?" could lead to a discussion of the breacan feile.
• Do any of us play the "traditional" (i.e., two droned) instrument?  Wasn't there a traditional one droned instrument first? 
• Is ceol beag traditional?
• Even the "humor" regarding the tradition of "what's (not) under the kilt" results from a change in traditions in the time of Queen Victoria.  Undergarments weren't generally worn before then.  That is to say that underwear was not traditional...at least not for that point in time.  Part of the reason that the Scottish regiments go "regimental" is that it isn't a part of their history to wear shorts.  I don't know why the highland regiments haven't fallen in with what's traditional today.
• Perhaps the oddest "tradition" I've been asked about is something about the bride carrying a horseshoe at a wedding.  My understanding is that one was given to a society bride in the 1940's and some people now consider it to be "traditional".  Is 1940's old enough to be traditional.
• What about synthetic drone reeds and Gortex bags?  They are certainly a modern tradition.  It may be one you don't hold with, but these ideas are established, popular, acknowledged, recognized, accepted and are beginning to be handed down to the next generation of pipers.

For the most part, people generally use the word as a cute replacement for "customary" and "recognized".  That's how I always take the word initially.  Hence, when a traditional bagpiper is requested, I would intend to present someone dressed in a pleated kilt playing a three droned instrument.

There is a contingent who are more interested in the use of "traditional" as a substitute for "historically representative of some point in time". Some of these are very learned people interested in learning about how piping has progressed. One outstanding example of this is a book by Gordon Mooney entitled "A Scottish Wedding, Woo'ed an' married an' a': An Exploration of Scottish Wedding Customs" Traditional Music Books, Lauder, Scotland 1999.

There are also those who wish to argue about two droned warpipes, whether tunes we play are songs, great kilts and the glorious days of Bonnie Prince Charlie.  I prefer the far sweeter sound of my own drones...

I always recommend that anyone interested in traditions and traditional events, do what people before us have done - keep what is meaningful and add to it to make the event significant and important. Don't feel the need to retain that which is not of value to you!