I don't do a traditional seal because my hair doesn't like straight oil/butter. I do use a minute amount of really rich product as one of my layers, which I think does the same thing as sealing. It frequently takes my hair a few hours longer to absorb product after it's dry. Don't think that's a bad thing. My hair gets better throughout the day.
With so much hair, you may have a really difficult time maintaining your curl. It's a lot of weight and that pulls out the curl. You may have to consider a trade off--hair that's shorter and maintains it's curl, or the length.
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3a (Corkicelli), highlighted, fine, low porosity
modified CG, since April '07
CG since 3/11/08
SE PA
HGs: Curly Kinks Satin Roots, Curlycue ReNew and Coil Jam; homemade FSG and okra gel; soap bars; DM MiraCurls Curling Gelly; UFD Curly Magic; Shescentit LIs; Sevi conditioners; Botanical Spirits Puree, CJ Repair Me