The problem is not unique to the dory or to the lug rig. It is fairly common in a great many sailboats. Sailing downwind with substantial following waves increases the risk of broaching. See this entry from Wikipedia -- Broach (sailing). But maybe the threat of broaching was not the problem you were experiencing?

For what it's worth, my opinion is that an open boat is best sailed in protected waters -- inland lakes or intracoastal waterways. I'd like to be able to get to shore somehow. Being blown out (or carried by the tide out) to open sea does not appeal to me at all.

Respectfully, I suspect that the problem had more to do with boat set-up and skipper ability, especially since you admit to similar problems in docile conditions.  While Birch2’s comments are true, sailing downwind in 1-2’ seas should be solidly within the “really fun” portion of the NED’s ability.  If it was the wind that was giving you problems, putting a reef in or even dropping the sail and going downwind on bare pole should have restored full controllability.

My first suggestion would be to take a few sailing lessons if you have not already done so.  Ideally, you find somebody with lug rig experience who can spend time on your boat, but good instruction on any small boat will be worth the effort regardless of the rig.

Next, I would spend some time reading about how to get the most out of lug rigs.  Here is an excellent source:  https://www.storerboatplans.com/category/tuning/lug-rig-setup/

Lastly, you can probably get good advice here if you post a more much descriptive narrative regarding the problems that you were having.  How experienced are you?  How high were the winds?  When you say that you have directional control problems, what was the boat doing?  Etc.  Pictures and or descriptions of how you have the lug rigged would also help.

One general comment that may or may not have anything to do with your situation.  During my time as a USN sailing instructor, the number one problem that novice sailors had in higher winds was downwind in higher winds.  The tendency is oversheet the main and to not properly tension the sail (luff, vang and outhaul).  That combination creates a lot of weather helm which can cause the boat to round up.

   Mark N, appreciate the comment. I'm pretty much self-taught with aid of books, and experience on inland lakes. Probably not enough for these open sea waters, so I will follow your advice. The outhaul and downhaul on the sail were as tight as I can make them, and the traveller was set no more than 1 ft over the rails. When I noted the problem I really couldn't take in the reef without risk. The winds were 10 mph going out, but at least 15 coming back, according to the local channel. The winds were coming from the SSW, and I was trying to track to the N, but couldn't maintain the course, being constantly blown to the NE. I couldn't lower the sail because the towboat wouldn't be able to find me in the whitecaps. I was about  a mile + offshore. Fortunately the iphone gps could give the towboat the needed info.

   I have no experience with the dory but sailed a small catboat on Buzzards Bay for years. In those conditions I would let out the peak halyard to twist the sail, depowering the top of the sail. I would also raise the center board which would greatly  reduce weather helm.

The dory has nowhere near the rudder area of a catboat so you may have to move your weight aft. Buzzards Gulch can get pretty “sporty” when the afternoon breeze comes up so you need to drop everything and row.

   That should be: you MAY need to drop everything and row. 

I think you may want to stay in more sheltered waters until you are more comfortable with the dory under different conditions.

It is easy to get yourself in a box like that.  You head off downwind with the wind rising, but it doesn't really feel like the wind is all that much.  You end up galloping along with too much sail up and the boat getting out of control as the waves start to get big enough to add to the steering issues and, eventually, threatening a broach.  Bringing her up on the wind now seems an iffy business, because a long, skinny boat like that doesn't like to get caught broadside to big waves.  I know the feeling.

Rigging a drogue like kayakers or fishermen (or folks fishing from kayaks) use would help you get the boat head-to-wind and slow your drift so you could more easily get the sail down, get in a reef, collect your wits, bail, have a cup of cofee, etc.  If you need visibility, replace the sail with a distress flag, which you ought to have aboard.  If you're not in distress, but simply having a rest, just hoist Old Glory and try to look calm.  <;-)

Be careful out there.

.....Michael

   I think the NE Dory and the Skerry lug have some characteristics in common.  The NE should be a bit less tender due to overall larger size, but both have narrow waterline, displacement hulls which are very easily driven or over-driven.  I've posted a couple of times on my learning curve w/ the skerry.  My last boat was a big keelboat and the dinghies before that were planing hulls, so it's different.  As you found out, downwind creates a large helm moment that's hard for the rudder to counteract because you have one large sail with most of its area on one side, causing the center of pressure to be out over the gunwale.  The NE has a shallower rudder than the skerry's kick-up rudder, i think, though there are threads here about deeper rudder mods for the NE.  See about my previous experiences here:

https://www.clcboats.com/forum/clcforum/thread/44613.html

and here

https://www.clcboats.com/forum/clcforum/thread/36452.html

I was able to drop sail, basically just letting it flop and hauling it in the boat.  Then I could get the reef tied in and rehoist and life was better.  The boat drifted downwind lying a-hull just fine in 2' Chesapeake chop.  The second time, I had the reef in but got surprised by the wind funnel between a headland and a rocky island w/ only 100 yards in between.  Since downwind was the direction I wanted to go, I basically wound up letting the sail "weathercock" over the bow and drag me down wind until I had the room and lower breeze to sort things out.

I've yet to hoist my first sail yet but I have used a drogue and it's a dam handy item to have. I certainly  plan to keep one handy at all times I'm even considering making a smaller version to run off the stern to prevent broaching when entering  a rough inlet.

   Was wondering has anyone tried some sort of oar lock off the stern to use an oar as a rudder and for  sculling in tight places.i see that the surf rescue boats use something like that 

   It’s kind of amazing how often this happens.
This month’s edition of Small Craft Advisor has a great article on boat trim and sailing. Dudley Dix, On Design discusses effects of boat trim on helm control. Might be a good supplement to this thread.

I got caught out in Lake Pymatuning in my Skerry in a 20 to 40 mph blow arising from a sudden severe thunderstorm.  I was a mile from shore and 4 miles from my return destination. I dropped the yard, and rested both it and the boom and sail in the boat.  I pulled out the daggerboard. I sat on the middle thwart facing aft and sideways.   I was getting blown southwest, and needed to go southeast.  Forget sailing.  Not a chance.  Using the rudder and oars, I was able to deter the boat's course enough to avoid getting blown into shore to starboard (southwestwards) until I found a sandy beach and allowed the Skerry and I to get blown in there, while also rowing rather forcefully, so as to make it to the beach and wait it out.  I was glad (and proud of the Skerry) that none of the waves that were overtaking the boat as we drifted south were coming into the boat over the aft gunwales.