You read this all the time on ad campaigns of cellular companies “fair usage policy applied”. The very much is true for 301 redirect option search engines like Google & Yahoo provide you so that you don’t lose the effort you did on pages or domains that you are not going to use anymore. The best way to do a redirection of your old domain or URL to a new domain or page is using 301 redirect, which is in accordance with the SEO principals and doesn’t hurt your SEO effort on such changes. That’s the primary or “fair” use of 301 redirect as opposed to 302 direct which means the page has moved temporarily. 301 redirect tells the search engines that a specific URL or domain has been moved permanently to a new location and thus clicking on the old link that you find during your search will take you to the new redirected page instead of giving you a 404 error page.
301 redirect is very handy technique and used quite often by many webmasters to point their old sites to a new domain, multiple domain names to one main domain (for example xyz.net to xyz.com), or a URL that is no longer working or required in a domain but has been indexed by search engines and still bringing some traffic. I had experience of using 301 redirects in the past on several of my sites when I developed for example subdomain instead of a folder for a particular keyword. Also, I do run a job portal and once we moved the whole site to a new technology, it was quite tough to synchronize all these pages to the new ones and there were thousands of job URLs appearing on the first page of Google for long-tail phrases (specific jobs in specific location etc). So the best way out for me in that case was to make a 301 redirect of all the old site pages to the new site homepage assuring at least that the customer landed on my new homepage instead of receiving a 404 error page which could be major turn-off for a first time visitor. However, I had to mention through a pop up message screen that the site structure and URL has been changed so a visitor doesn’t feel that he has been taken to a wrong page.
On the positive side of it, many of SEO webmasters use 301 redirect to strengthen the link building authority of their landing page by redirecting several of their authority pages of different backlink profiles. As said earlier in my “think human, think Google” post, that it’s better to be natural and do things the way they should be done. As 301 redirect was not made for bringing link strength from different pages to a landing page, in my opinion using such technique, even though its allowed and being practiced widely, should be avoided. This is just to make sure we don’t annoy search engines with our derivative of benefits where we will bear the brunt with unexpected algorithm changes all through the year and no one will know legitimate from illegitimate in SEO best practices.
One last point to consider while you are doing a redirect of multiple pages to your landing page, that all the anchor text used in backlinking profile of all these pages must be present on the new redirected page, at least in the content, if not in the META. This way, the least I can assure you that you will not lose the affect of your linkbuiliding strength coming from multiple pages that were redirected to your landing page. Just to make it easy, for example if you have this page abc.com/my-product.html that has a backlink with an anchor text “my product” and you are redirecting it to your main page abc.com. Just make sure that the phrase “my product” is there in the content of the homepage. This will help you maintain your SERP for that keyword and preserve 90-99% of backlinking profile of 301 redirected page.
To conclude, the only fair usage of 301 redirect is when you are moving a URL or a domain name permanently to another URL and not to strengthen the landing page authority by using the backlinking profile of the redirected pages. Let’s give search engines chance to develop more user-friendly technology for the net surfer rather than fighting unfair usage and twisted SEO efforts adopted by many of us.