What if handwriting is changed deliberately?
When a man attempts to change his style of handwriting he simply alters the principal features of it. If his writing normally slopes to the right, he will probably adopt a backhand. He may also use a different kind of pen; may change the size of the writing, alter the customary formation of certain letters, and add certain unfamiliar flourishes. But knowing nothing about the many minor characteristics of his natural writing he unconsciously repeats them, notwithstanding his best efforts to veil the identity of his chirography. In this respect, he resembles the actor, who, while he may assume all the outward characteristics of another individual, still retains certain personal peculiarities of which he is himself unaware and which render it impossible for him to completely disguise his own individuality.
Source: Graphology or How to Read Character from Handwriting BY SIMON ARKE American Institute of Graphology 305 Lenman Building Washington, D. C. 1903