Depends. Bermuda to USA is easy to DR, all you need to do is proceed sort of westbound until you get a decent AM station and then figure out where you are 
The other way, not so much. You can be on the reefs before you see the island and there are a lot of wrecks on said reefs to prove that out.
Back before GPS or even compact LORAN was a thing and I wasn’t old enough to drive my job was “RDF Boy”. It was easy enough to keep your latitude north of the reefs with a sunsite and wait to pick up the beacon from Saint Georges and follow it in. Apparently I got along with the RDF better than anyone else.
… and if found straight… see, that there is neither a port nor a bunker station…
That’s what I’m saying. The argument for staying proficient with celestial is in case the GPS signal is lost. However if it is lost mid-ocean just shift to DR, plenty of time to sort things out.
On the other hand the risk of 100% reliance on GPS in a tight, heavy traffic pilotage waters can be mitigated by maintaining proficiency with radar/visual navigation.
Tall claim without radar.
Now that’s poor passage planning 
There’s both a breakwater and a tanker terminal in Rupert’s bay, though. I’m sure they’d sell you some if you ask nicely…
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To answer your original question in a different way: The problem with DR is that a high level of skill and vessel familiarity are needed to achieve decent accuracy. The seafloor is littered with those who discovered this to their detriment.
About a million years ago was on a ship after going through windward pass toward crooked island pass. The last sort of good position we had was a 24 mile radar range from cabo massi, a loran A line, and an advanced sun line. Nothing but clouds next 80 - 100 miles give or take. I remember really looking for Castle Is light, and needing to find it before we went on. Told that story years later to some folks and they were having a hard time understanding we didn’t always know exactly where we were back in those days.
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I remember that on one occasion, after almost a week of stormy weather with no sun or stars, the captain called for what was named a ship’s council which was held in the chart room. The subject was the ship’s position.
Everybody was invited to give their idea about the ship’s present position and the reasoning how they arrived at that. Somebody then asked the captain what his idea was. He didnot hesitate but put his big paw on the middle of the chart of the Atlantic and said: “I think about here!” Roaring laughter…
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When I first started sailing early '70s, I was privileged to be on a delivery crew bringing several OSVs to the North Sea and Med. The mates on most of the trips were retired United Fruit Company masters. These guys were phenomenal. It was not uncommon at the time when there was total overcast for a few days, vessels coming in close contact would compare DRs. These mates would never admit to doing this as one said “he would never bum a fix!”
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If you can see a faint shadow on the deck, you can take a sun line.
Just saying…
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If you have a horizon. If not you’d need a bubble sextant.
I rely on my “seaman’s eye” 
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You must be level headed!
Quite the contrary. Rather off-kilter or so I’m told.
My sun lines are fucked
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DR in the bahamas, all flat, radar no help?
In my experience on deep-sea ships there is no company policy to practice celestial in order to maintain proficiency in the case of GPS signal loss.
I agree that from a standard risk management point of view, not having such a policy is correct. There should however be a policy to maintain proficiency in using visual/radar because the risk is much higher in pilotage waters.
That’s not to say that DRs are appropriate in all situations.
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At the moment and since 2016 the U.S. Navy has a new policy in place and brought back again navigation by the stars for officers after it was phased out more then a decade ago.
The Navy and other branches of the U.S. military are becoming increasingly concerned, in part, that they may be overly reliant on GPS. The system can be rather easily switched off, destroyed or jammed.
Not saying it should not be taught. I would think most officers could hack out something within a few hours of losing GPS. Surely within 48 something solid. Not going to need a six star pinwheel.
Meanwhile there is the method of DR. Which Colulmbus used btw.
The Astrolabe.
Quite true. He tried out the Octant and Astrolabe but that didnot work out, errors of 20° and more. He had to solely rely on DR during his voyages with only his trusted compass. Let’s sail West boys…
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AFAIK the whole narrative that the U.S. Navy dropped Celestial due to over reliance on high tech is incorrect. The QM rating in the Navy always retained the ability to use celestial.
Quartermasters Keep Navy on Course
“I couldn’t have imagined any of these advances back in 1998,” said Warden. “Now there’s VMS (Voyage Management System), which lets you set the voyage points electronically. It feels like a video game to me, but it shows how far the equipment has come.”
VMS digitally plots and shows the ship’s position, course, heading, speed and depth over a digital nautical chart. However, quartermasters are still required to be familiar with older tools of their trade.
“A QM still has to be familiar with the many aspects of their job, whether it’s celestial navigation, using paper charts or manual navigation,” said Bembry.
Don’t know about the Navy but I never saw a CG officer pick up a sextent. That was back in the 70’s.