this is not true. infact almost all seo gurus recommend the plugin. but probably for better results you might just wanna purchase their paid version. or you certainly could use both headspace and all in one seo plugin.
Weird way to start a thread bud... "There's no salt in the ocean. I know it. Prove me wrong" later... "So... does anyone know if there's salt in the ocean? I can't figure it out". What?! Lol
I heard wpSEO is way better than All-in-SEO. Personally i am on AIOSEO But never had such issues though.
I use the same AIOSEO and my blog is ranked in the top 10 of Google, in fact in several of my keywords. So obviously it works. I use it in all of my WP Blogs.