a about a month a go i had a rock hit my windscreen in my forester, in some road works. because some inconsiderate driver was not doing the 40kmh

any way i did have it patched up but the guy said due to having moisture in the crack it didnt work very well (he didnt charge me for this).
so now we are getting into winter and some frosty mournings already in Ballarat my chip has already turned into a nasty crack.
so my question is, other then visiblilty issues, is a cracked windscreen dangerous? the crack cannot be felt on the inside just the outside.