Tiefling Arcanist: bloodline and fiendish sorcerey

[Yoshua]

if you take the exploit bloodline development and select abyssal or fiendish, does that mean you can then benefit from fiendish sorcery?

[Fearspect]

You aren't a sorcerer, you just have a sorcerer ability. You also couldn't select a feat that states 'Sorcerers Only', for example.