We are currently looking into improving our TTFB on our ecommerce site. A huge improvement would be to asynchronously load the product prices on the product list pages. The product detail page – on which the product is ordered- will be left untouched. The idea is that all content like product data, images and other static content is sent to the browser first(first byte). The product prices depend on a set of user variables like delivery location, vat inclusive/exclusive,… etc. So they would requested via an ajax call to reduce the TTFB. My question is whether google considers this as black hat SEO or not?