Hi,
The attribute minimums reflect requirements the various training academies and such use to weed out those they deem unworthy of entry, kind of like how most modern military and police forces tend to have physical requirements for height, weight, and physical capabilities before accepting an applicant. The Clans lack a requirement because the only legal way to get Clan armor training is to be born to the Elemental Phenotype and undergo Elemental training, which tends to beef you up to Clan specs.
That all said, it is therefore possible to through a 98-pound weakling into a suit, if he's trained in its use. If not, well, some fun options appear in AS Companion, p. 57.
Thanks,
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