i don't think anyone has really considered the iceberg and its effect on the hull. the bulk of an iceberg ( 90%) is below the water, yet that particular iceberg was high enough out of the water to deposit ice on the decks.. and folks looked up at the iceberg. For me it says the stress on the titanic's hull, was likely to be much more than the parts that gave way and let water in, and there is supposition that the titanic just grazed it. i don't suggest that the water coming in, was anymore than what is known, but i do think much more of the iceberg was in contact with the titanic , simply because the amount of the iceberg whatever its underwater shape might have been was so large it simply wasn't just pushed out of the way by the titanic.. it was equal or more than it.? How that collision affected the hull, isn't easily researched now, but i do think the iceberg may well have effected stress damage, - flexing, sideways if not upwards as well, that did the titanic no favours.