Except it's not humanoid.
And, as has been pointed out, the line about atrophied arms and only getting 1/2 Strength to carrying capacity because of those atrophied arms indicates that Strength is arguably restricted on everything you do with the arms.
At best, it's something that needs DM clarification. At worst, it's something potentially crippling for any melee type.
That said ... getting to Large for a third RHD probably is something we should give DMs a heads up about.