This paper assesses the ways in which the instrumental-professional translation subcompetence (PACTE 2001) can be complemented with strategic and extralinguistic subcompetences to optimize results in scientific and technical translation courses. The focus is on those aspects that pose an obstacle to the development of quality products. In a second part, different documentation strategies are analyzed to find viable ways of predicting potential translation problems, of using translation strategies and, and of enhancing text revision and edition. The methodology used is a descriptive approach to quality assessment from a textual-pragmatic-cognitive perspective. Evidently it is difficult for the translator to improve his/her strategic and extralinguistic subcompetences if his/her electronic documentation and search strategies do not respond to the quality parameters specified, and such strategies should be complemented with a knowledge of traditional documentation sources.