Close. Any time a pokemon player references a "tech," they mean a single card within a deck meant to help deal with specific situations that might occur once every few games, or situations that might occur once per game. That is, the card is less universally useful than most of the deck, but can be vital if one particular situation comes up. For example, a grass deck may wish to run a "tech" water pokemon, in order to balance itself should it have to face a water-weak fire deck.
The most common "tech" cards are trainers. In this format, a "tech" buffer piece might very well save your pokemon the turn before it gets knocked out, but you wouldn't want to play a buffer piece at just any point in the game. You would want to play draw cards as often as possible, so they're not tech. Same with the primary energy you'll use to power your pokemon, or the main line of your pokemon.
Hope that's helpful,
Dendro
Team Leader of Team Stunky, Pokebeach Strategists
