Everyone's seen it.  There are thousands of articles out there giving hints
on how to beat this archetype or that archetype.  Sometimes they have good
tips and sometimes they go out on a limb giving all sorts of hairbrained
strategies that have 1:1000 odds of actually working.  The truth is, most
people just DON'T understand how to metagame correctly. 
    Most people metagame by focusing their deck particularly on the
destruction of 2 or 3 particular pokemon.  Unfortunately, there are plenty of
variations in what pokemon people use, even in something as boring as
haymaker.  So, the chance that these decks will actually kill the deck you
face is, well, slim.  Here's an example.  Your metagame is Fighting-Centered
Viagra decks.  You decide to build a Psychic/Fighting deck to counter your
opponent's Hitmonchans and Wigglytuffs.  You then build a Hitmonchan Sponge. 
Unfortunately for you, your first opponent plays a Haunter Agility deck,
something he or she though up on their own.  Since all your pokemon are weak
to theirs, and you have a hell of a time countering since you only do damage
1/3 of the time, you end up losing (prizes) without on KO.  Too bad you
metagamed instead of using that Toxic Nidoking deck you left at home. 
    So, instead of playing counter cards, how do you metagame?  Well, to
start, you need to look at the components of your deck.  There are three
major components: Trainers, Pokemon, and Energy.  Each need to be manipulated
to fit your metagame.  First, some trainers are more necessary if facing
certain types of decks.  For instance, if Damage Swap is your metagame, Gust
of wind and lass may find their way into your deck.  Similarly, if energy
intensive beat-down decks are your metagame, you may choose to pack a lot of
energy removal and Super Energy Removal.  However, do not include cards that
have absolutely no use unless you are fighting that exact type of deck, make
sure that your trainers are versatile, and will be of use NO MATTER WHAT TYPE
OF DECK YOU ARE FACING.  There is nothing worse than having a poke flute when
facing a Viagra deck.  Second, your choice in pokemon should be based only
loosely on your metagame.  For instance, lets say you plan on playing a
Status Effect deck.  You were planning on using Beedrill, but reconsidered
after realizing that there are just too many Mimes (your metagame), and that
Beedrill will end up being useless against them.  Instead of throwing in
Jigglypuff and so forth (the common anti-mime prescription) you choose to use
Nidoking.  Why?  Because he is similar to Beedrill, but CAN kill Mimes.  Most
pokemon have a similar double out there (these are particularly obvious in
those annoying "cheap replacements for rares" articles) and often that double
will be able to do something that your original choice can't.  So, the key
concept is DON'T CHANGE YOUR WHOLE DECK CONCEPT WHILE METAGAMING, SIMPLY
CHOOSE SIMILAR POKEMON THAT CAN DEAL WITH THE METAGAME BETTER.  Third, energy
is the least complex item to tweak.  Simply, if energy removal and E.R.
pokemon are common, play higher energy counts and less D.C.E.  If everyone in
your area thinks E.R. is for lamers, then use more D.C.E. and a lower energy
count.  You may choose to use F.H.E. if you have a large number of Status
Effect decks in your area, or Potion Energy if most of your opponents use
weak attacks (why they would, I truly don't know). 
    So, simply put, do not go off and center a deck around specialized
"counter-pokemon".  Instead, include pokemon that will KO the more common
pokemon/deck types without changing your deck concept.  Trainers should be
versatile and should be of use against any deck, but particularly potent
versus the metagame.  Energy ratios should be manipulated if you have a
problem with Energy Denial, while certain special energies should be included
in certain circumstances.
                                                -FossilMagikarp
                                                email:  Edestus360@aol.com