It just takes time to learn the color and pattern genetics. I didn't learn overnight, but just by experience and research. It won't be long before you understand it all. We are lucky, we only have certain color genetics to learn, unlike other breeds, where I know I would be lost for a long time.
There are several different color charts to help with Ragdolls, and they are all great, but the best to begin to learn with is from RFCI, http://www.rfci.org/genetics/color_chart.php
It is really also great that Dante' is a high mitted, as I have heard from other breeders that breeding a true bicolor to other genotypes of bicolors can really throw too much white. If you choose to keep Dante' as your only stud, you could get a mitted female and throw both bicolor and mitteds, or breed him with another bicolor and get all bicolors, with the exception of breeding a high mitted and True bicolor, which could give you bicolors and mitteds.
I can usually sex kittens as soon as they are born with fairly good accuracy, but I have still made plenty of oops' along the way.
Usually, I think a girl is a boy, and after a few weeks I figure out it is a girl. Although, I believe with Kiara's litter, I thought I had 2 girls and 2 boys at first and one of my girls turned into a boy over night.
Some breeders aren't as excited about genetics as I am, so Dante's breeder may just know from experience now what her lines produce and not want to go into the research of color or patterning. While her lines may not produce chocolate, she didn't realize that when put with other lines that carry dilute's, a chocolate can occur.
I won't at all, claim to know everything about Ragdoll genetics, I am still in learning mode, but if you ever have any questions, feel free to ask. If I don't know the answer, then I will try to figure it out, and learn something new myself.
I am planning on focusing on my Seals and Blues right now, but I do hope to go into chocolates and lilacs in the future. I want to take my time, as a lot of the chocolate and lilacs were brought in by outcross, so finding a breeder who has taken the time to work with the lines, and put the outcross further back in the pedigree is important to me.
I hope we get new pictures soon. (Hint, Hint, wink, wink) How is the weather up in Maine? We have almost hit the 100 degree mark down here.