According to T 21/81
(OJ 1983, 15), it had to be regarded as forming part of his normal activities for a skilled person to select, from the materials known to him as suitable for a certain purpose, the one which was the most appropriate. The skilled person should therefore be at liberty, within the constraints of standard technical progress, to use alternative means known by him to have the same effect (T 324/94
). In T 410/92
the board also held that using higher-quality materials in the design of single-phase synchronous motors with a double-pole permanent-magnet rotor was obvious. The appellants had argued that the skilled person using the superior materials available to him would be confronted with baffling starting problems. The board however concluded that the skilled person's encountering known problems when using newly developed materials would not deter him from using them in order to achieve specific, desired improvements, particularly since the means of overcoming such problems could be derived from the prior art.