Well, yes and no. I just went back to my books...reading Reflections by Walt, W2DU. Your matching network, by the Conjugate Matching Theorum.....provides an impedance match - and 'tunes' the antennna system to resonance. Now, the there are two factors here. First, you have to look at question. The antenna does not have to be 'resonant' itself to be efficient, but that is not the only condition in a practical situation. If you have a lossless transmatch and lossless feedline, and lossless radiating elements, then a non-resonant antenna will radiate all of the power. (it might not have the pattern you want). So, if your 80 m dipole is 5:1 at 3.95 MHz, using a transmatch on a short feedline of heliax will make your non-resonant antenna efficient. Your transmatch, and the feedline, and the antenna will be in resonance when you are 'matched'. The 'system' is in resonance. That is the only way that the network composed of the transmatch, feedline, and antenna will take maximum power from the transmitter. Of course, the 'antenna' itself is not in resonance in the above example.