Interlinking Sites On The Same Box

Hi everyone,

I was thinking about running a couple of sites and have them interlink with one another for SEO purposes. I was thinking about getting unique IP addresses for each site but I read this comment on the hostgator forum "Of course, hosting with different IP addresses does nothing for you unless you have an SSL certificate on each of the domains. The search engines still know you have all of the accounts on the same box. "

So would it be pointless for me to do this? Would this method only benefit me if I had each site on totally different IPs AND servers?

Thanks

get a lot of cheap virtuals and link rather a-b-c and then c-a than a-b b-a