Effective use of Linking in site credits

[DXL]

I have dozens of sites floating around with a site credit linking back to my company's site at the very bottom of each page. For years the credit link appears as: Website Design by MyCompany, with the name of my company hyperlinked back to my site.

In Brett 26, its mentioned that its significant to hyperlink an important keyword on your site to a major site. So how important is the opposite, if I were to add a credit line to each site reading "website design by MyCompany" and link the words "website design" rather than my company name, back to my company site? Despite having dozens of sites linking back to my own site, my rankings have been lousy for several years. Should I be doing something different with these site credit lines?

[martinibuster]

Look at what you are trying to rank for and search the backlinks of your more successful competitors. Sometimes it takes a thousand or many thousands of links to rank better. Also, your IBLs might not be relevant to your site so it's likely getting dampened and not counting for as much.

[DXL]

Also, your IBLs might not be relevant to your site so it's likely getting dampened and not counting for as much.

I don't understand exactly what you mean by this.