Yes. Grapeseed oil has the highest burning point from a lot of oils. You won't reach this with a flat iron... Also grapeseed oil sits on the hair (doesn't penetrate it) and protects it.
This combination is well known heat protectant and has been used by many people for a long time.
At hip length, going for mid-thigh!
M MP HE HD (med text, med por, high elast, high dens)
Clarify: Nivea Intense Repair
Lo-poo: Nature's Gate CR
RO: TBS Rainforest Moisture, etc
LI: Elvive volume collagen, KCKT
Seal: Grapeseed oil
Gel: Kiss My Face
PT: EO Keratin co
Hair growth stim.: JBCO+EVCO
iherb.com 5-10$ discount code: VHT541 Many natural hair products!