The boy was NOT happy but in the end he relented because he saw that otherwise the girl wouldn't marry him. When the father saw the handwriting he was quite impressed. The handwriting analysis indicated that the boy had a gifted mind and exemplary character ["great middos" in the vernacular]. The father agreed to let the shidduch go through and a wedding was planned. Shortly before the wedding the boy started feeling very guilty. It turns out that he had submitted the handwriting of a different boy who was a masmid and tremendous baal middos. His question was is he obligated to reveal his trickery which would quite likely cause the wedding to be cancelled.
In will not tell you Rav Zilberstein's answer because לעניות דעתי it's PASHUT that he must tell, if not according to the strict letter of the law then certainly according to the standards of mussar and derech eretz.
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Can we trust graphology? This brings me to my personal history. About 20 years ago I went to a graphologist and in MINUTES it was clear that this man knows me better than anybody else in the world. He saw it ALL! All from my messy handwriting. I was blown away.
Some time later I met a young lady whom I considered marrying. I took her to him and had her handwriting analyzed and once again - SPOT ON! I brought her to various Rabbanim for their "haskama" but what he saw they didn't see. [Note: I won't tell you if I married her but I will say that she is the mother of my children and is presently in the kitchen washing the Shabbos dishes under the assumption that I am working on the Shev Shmatsa. If she reads this she will know that I took a break to blog about graphology. Hope she still likes me. Anyway, we see that the graphologist gave a great report.]
Sixteen years or so later I was having issues with a child of mine and I brought in his handwriting to find out what was going on inside of him. Once again - a precise characterization. Punkt! [Exact in Spanish].
I found all three visits extremely helpful. Know thyself. Know thine Kallah. Know thine child. Three huge boosts in Avodas Hashem.
In my opinion graphology is one of the wonders of creation and should be used to our advantage. I actually considered studying it myself but there are SO MANY Rebbe Akiva Eigers I want to get to so I don't think it will happen.
It costs but it's worth it. Oh - and make sure the graphologist has a reputable name.