During the Q&A portion of a Google Office Hours hangout, John Mueller answered a question about 301 redirects.
An SEO professional asked about using 301 redirects. They explained that their dev team does not like to use 301 redirects and would rather use 302 redirects.
The reason for this is because 301s are stored in browsers potentially forever. Their team explained that in the case of a misconfigured redirect, people may not ever be able to lose an incorrectly processed 301 redirect.
Their main question is: how do 301 redirects work on Google as opposed to browsers?
The second part of their question involved cache control headers. Can they get the best of both worlds by using both?
John explained that the entire crawling and indexing system is different from browsers. They are optimized for different things.
For example, when it comes to a browser, it would make more sense to cache things for longer periods of time.
From Google’s point of view, on the crawling and indexing side, they have different methods and different things they have to optimize for.
Therefore, they do not treat crawling and indexing in the same manner that a browser normally does.
He expounded that it is a bit weird, though with their processes in place: they tend to render pages in exactly the same way as a browser. However, the entire process of indexing content in their systems is very different compared to what a browser would do.
On a browser, this behavior won’t happen. But that’s where it’s different.
John also added that yes, they can use 301 redirects with cache control so they can get the best of both worlds in terms of cache processing.
He explained that it doesn’t matter which type of cache headers you add on top of the 301 redirect.
If it’s a solution that works well for both you and your dev team, then why not use it? He thinks it’s a fine solution to do so.
This happens at approximately the 22:09 mark in the video.