Working from this: *...dynamic clock or meteo widget on the page could boost the SEO... ...has been updated with new content.*

Short answer? No. Not even close.

Search engines, using more than one page, can determine patterns within the HTML DOM model that separates the header, footer, sidebar, and any other page element that is truly **not** content. The idea is to evaluate the content and not things that do not add value to the content directly.

*Let's assume for a moment, that the "clock" is within the content itself.*

Search engines do not look at content in a linear way. It can't. Computers do not read and cannot evaluate what *they see* in a way that humans can. For this reason, the evaluation of the content uses semantic analysis including semantic topic scores, semantic linguistics, and others to evaluate the content itself. What Google, in particular, *sees* would be small changes in content scoring if at all. These methods adequately handle restructuring and reordering of content, spinning content, keyword stuffing, content gibberish, and any other trick that was designed to deceive search engines.

Content has to have meaning. Adding erroneous elements that do not add meaning do not add value. It is that simple.

As a warning, please do not follow the advice of junk SEO sites. There are too many of them. There are no tricks that work. Any SEO advice that is even hinting at an advantage outside of creating compelling, well written, sought after, and well structured content is very likely leading you down a very foolish path.