Heave /Hove to -what are the limits?

[Cheechako]

Anytime the seas are greater than the wind, they drive the bow down. Water force is far greater than wind force. Water will bend lifeline stancions right over. Wind wont.

[zeehag]

heave to--comes from heaving your boat to the weather. is shortened.
sea dreaming--you will be coming down soc-- while you are in middle away from everything, start fishing. when you go to boat your fishie-- put your boat in irons. practice that.
th epardeys cruised an engineless boat. dragging and towing stuff worked for them for that reason. it doesnot work same with a propellor sticking out th e end -- things get befouled. use caution when practicing that one. mightr wanna wear wet suit por dry suit for that exercise, and bring a cutting instrument on your dive. funny how lines are attracted to propellors.
you will be able to see sudden squalls well before they GET you. you will have time to either anchor in the lee of a shoal or island or in a cove before it hits. btst age 9.
learn what the sky looks like when squalls hit. that is your best knowledge-- eyeballing the weather. constantly. you will not be heading out when a cane or ts is predicted.
for weather--as my boat is heavy and able to sail big winds--i sail until i find th ecalm--it will overtake me. then i head into a port and dock the boat. no sense in killing self over nothing.
each of us finds different ways to do stormy weather. i sail thru itif i can--small storms. i had a hailstorm april 2011 on my way south from sd-- at salsipuedes my prefrontals had passed me leaving me in the calm before the storm. ok. engine on, motor into ensenada and berth boat. easy peasy. about an hour or two later--i was asleep--the hail stones woke me. good timing. pat self on back, turn over and prolly snore.
if you sail norther in soc--the seas are big boxy and closely timed--get into a safe anchorage. wont be fun'
weather is predictable far enough in advance of departure you can time your passages with and to them. crossing puddle--- not so much.
but you an learn a lot by playing with your boat in soc on your way here. just make sure no islands jump up at you-- mexican jumping islands happen, mostly closer to shore,
both sides of sea.
back to my original thought--once you place boat in irons, you can figger out how it likes to sit while stationary. each boat works it differently, depending on trim and hull.
i know i didnt exactly answer--but you will know when you do it. your boat will sit fine and pretty and you can play with it.
to get boat out of irons is easy-- pull the appropriate headsail sheet and continue on.
ps---oil willnot fix big boxy seas caused by northers. it does help the smaller chop caused by some of the wind. oil on water is only good for tender/ dinghy to mothership exchanges of personnel and goods. not for sailing.

the heavy weather sailing i did thru severe thunderstorms in gom and severe fronts in a lightweight not so sturdy performance ha ha ha cruiser, in gom was-- use engine, find a comfortable not bashing point of sail (about 7/8 angle to the seas and winds) and keep on going. the storm/squall ends soon, unless it is a pacific front or named fornication.

[The Smokester]

A limiting case: In the conventional heave-to, the jib is back winded and the main feathered to orient the boat to wind and sea. This obviously produces a lot of windage and at some point, as the wind increases, the boat can be knocked down. You can still heave-to without the jib...with main only...and the boat is less likely to be knocked down.

[MartinR]

My humble opinion. Heaving to in heavy weather works well for long keeled gaff-rigged traditional work boats. I have done it many times, worst probably in Biscay in a force 11 and 12m waves. The boat was hove to under balance reefed main and a backed up storm staysail. Basically the boat is almost (not quite) side to the waves and drifts sideways at a couple of knots, creating turbulent water, that somehow prevents the sea from breaking. It is astonishing how comfortable the boat is under these conditions. But these boats are designed to do just this. I would never do this with modern short keeled boats, these need to be sailed actively in storm conditions, but this is much harder on the crew of course. Running is always a good idea if you have the sea room, but the yacht needs to be steered, and not by autopilot. And, the bigger the boat, the less the likelihood it will be overwhelmed.

[Seabeau]

I sail a Presto 36, a ketch rigged, internally ballasted centerboarder, one of William Munroe's excellent designs for shallow water. My heave to strategy is simple, pull up the board, drop all the sails save for a hardened down and reefed mizzen and tie off the rudder amidships. She drifts slowly aft, with the mizzen keeping her head to the wind. I go below for some reading or other diversion while the weather rages. The retracted board allows her to slide sideways if she's struck by a breaking wave.