Frustrating fonts serve a purpose:
A recent paper by Daniel M. Oppenheimer entitled, pleasingly, "Fortune favours the Bold (and the italicised)" delivered a blow to lovely fonts everywhere by demonstrating that we absorb information better when it is a little hard to read. It seems our eyes just skim over Times New Roman and Helvetica, but stick when we reach a smudged, cramped line of type, finally ready to engage. … To the experimenters this was a challenge to one of teaching’s basic assumptions – that when learning is easier, it’s better. Rather, adding a few superficial difficulties to the reading experience is more likely to make pupils engage with the text.
The Dish 