Safari still is a train wreck - freezes quite often
My experience with Safari is that the freezes that I experience are due to irresponsible insertions of a kind of advertising that we do not handle very well.
I've been in touch with the owners of vBulletin (Internet Brands) and they verify that it is due to irresponsible advertising that is inserted through Google services.
If this happens to you while you are on Mac OS, you are just stuck.
However, they've apparently found a way on their biggest Internet Brands vBulletin site to refresh iOS Safari automatically when such a problem is detected.
Unfortunately, this means that you will have lost a little bit of text if your site is not set up to automatically save text. Even if you're set to save text automatically, you might lose a little bit.
But, anyway...I am not sure that the problem you're experiencing is necessarily a problem with iOS Safari.