Bonus Attribute Point can be bought up to six times (well five if you go by the recommended limit), once for each Attribute. However, it can only be used to increase a single Attribute beyond the Racial Modified Max. It's clearly stated in it's description. The last sentence of the last paragraph of the edge states as much. There is no room to debate it. It's quite clear.
Exceptional Attribute can also be purchased only once per Attribute, but you can do so for each Attribute. Doing so increases your Racial Modified Max. The very last sentence of the edge's description states as much. There is no room to debate it. It's quite clear.
Thus for example, with Bonus Attribute x3 (Charisma, Intelligence, and Willpower), and Exceptional Attribute x2 (Charisma and Intelligence), a Human character can start with Charisma 7, Intelligence 7, and Willpower 7 as long as they bought all three at 6 to begin with. Just like Cochise said. In fact, it's the only legal way to do it without playing an Otaku or something similar.
I do tend to agree that it's a waste unless it's vital for the character's concept. But it's certainly legal.
