will google ban your sites if they found you are using more than 1 <h1> tags? Is it just fine if you put 3 <h1> tags on one page?
They wont ban you but it risks devaluing the page. Consider that with your stylesheet you can make h2 tags look like h1 tags Each page normally has only 1 subject, and then subheadings. It's a basic premise of most documents, web pages included.
I used to have several <hN> tags of all sorts long time ago and finally took them out - just to notice that all that didn't cause any differences in ranking at all, neither positive nor negative. From this I have the impression that G! simply doesn't look at those things at all - and will therefore not ban you either, if you use more than one per page. It seems to be as insignificant for G! as meta tags are...
I tend to work on the basis that use h1 once use h2 twice use h3 three times relax more with h4 and h5 and the h*, b, i, strong, em tags should make up a small amount of the page content. There should be more normal text than emphasised text...
Three <H1> tags isn't likely to raise any eyebrows for any search engine. There are times when more than one <H1> tag is reasonable and makes sense... just don't go nuts and overdo it.
I have been doing tests (Google, MSN and Y has not listed the test pages yet). Day 12: H1 and H2 ranked just higher than the meta tags but lower than all other test pages. Day 28: The only test page that ranked lower was "KW spammed in meta tags". Conclusion: H1 and H2 seemed to have a very low value but is still part of the algo.
I wouldn't do it if I was you. If you cannot justify something with a different reason other than manipulating search engines, it could possibly get you in trouble at one point. The best thing to do is to make sense at all times
I don't think the search engines are giving much importance to the Hx tags as of late. Furthermore, the H1, H2 and so on tags are just 1 out of 100's of factors that affect your ranking. Why not concentrate on other more important aspects like backlinks and site structure instead of feeble factors like h1? - (just my opinion) Perhaps you just need to do some testings for your industry and see.