Even 50 meters would be too deep for the wind to blow the water clear all the way down to the bottom. So the vast majority of the current Red Sea would seem to be ruled out as a crossing point. That leaves either an earlier version of the Red Sea (probably not the main body of the sea, but a shallower ancient northwestern arm), or some other body of water entirely, some lake or lagoon. I would suggest that the latter is more likely.
The average healthy adult person, walking on a flat dry surface, could walk the 5 km mentioned in the article in about an hour. However, we are talking about walking on a potentially very muddy bottom, which would slow things down considerably. We are also talking about (using the figures from the article itself) walking against a steady wind in the range of 60 miles per hour (to keep the passage dry for 4 hours; a stronger wind would be needed to keep it open for longer). It’s almost impossible to walk against a wind that strong, and even if one could, one’s walking speed would be only a fraction of normal walking speed.
Plus, according to the Biblical story, we are to imagine people carrying all their worldly possessions along with them, probably in many cases bearing loaded packs on their backs, walking with infants in their arms, pulling little wagons along behind them, leading heavy-laden donkeys or camels, etc.; there would be elderly people, pregnant women, children (whose legs are shorter and don’t walk as fast), etc. We aren’t talking about young men in their running shoes and jogging pants with hands free and no weights attached. So this group of people is going to move slowly at the best of times, and in this case, walking in potentially soggy mud which would cling and drag, and against winds which would exhaust even a very hardy young person after even 15 minutes of struggling. Can they really get across the passage in just four hours?
Another factor is the length and width of the column of Israelites leaving the country. How many thousand Israelites were there, and was there only enough width to march single file, or was there enough width for several hundred Israelites to cross at once? If they have to march single file, then even if the first hundred or so can get across in 4 hours, the last several thousand won’t make it.
Then there is the account of Pharaoh’s army being utterly annihilated when the waters come back. This could only happen if the waters came back suddenly, rather than gradually. If they came back gradually, then there would be time for soldiers near the west end to retreat back to dry land, and for soldiers at the east end to rush onward before the waters completely closed. Did the modelers of these scenarios consider only sudden drops of the wind from 60 miles per hour to zero, of did they consider scenarios with gradually slackening winds?
The question about the destruction of Pharaoh’s army (complete vs. partial) is important, because the whole purpose of such scenarios is concordist; it’s to show that the Biblical accounts can be correct without violating anything learned from science. The moment one admits, “Well, maybe a few hundred of Pharaoh’s men got across or turned back before the waters closed,” one is admitting that the Biblical narrative is slightly fibbing, and that defeats the concordist purpose. So one has to either bite the bullet and admit that the Biblical account isn’t entirely true, or one has to suppose an instantaneous drop of the winds to zero, with waters roaring back without warning, catching Pharaoh’s army too quickly for it to react. And even then, one has to assume that all of Pharaoh’s army was in the middle of the passage, too far from either end to escape. If any of the men were near either end, some of them could have escaped by swimming to shore. (Healthy men who know how to swim can swim a few hundreds yards easily, especially if they are in very light armor, e.g., archers. And indeed, it’s not impossible that there were men in the army capable of swimming a mile and a half, which means they could get from even the middle of the 3-mile passage to shore.)
Considerations such as these lead me to conclude that the writers of the article are “really reaching” to find scenarios that could justify the Biblical narrative. It just might work, if we are talking about a very shallow body of water, with a very wide crossing zone, and Israelites so pepped up by Egyptian-made chemical stimulants that they can fight against gale-force winds for three or four hours while carrying heavy loads, and the Egyptian army is entirely clustered in the middle of the lake and the winds suddenly drop from gale force to zero, with the water roaring back in a wall instantly. But this is really pushing things.
There’s another, more general absurdity in such “it all could have happened under purely natural causes” suggestions. Even if happened in that way, God would have had to go to incredible trouble setting up things so that the Israelites arrived at the site at exactly the right time to catch the geographical freak phenomenon. He would have to make sure that the Israelites left at a precise time and marched at a precise pace so as not to get there even an hour too early or too late. So he is still going to have to “intervene” insofar as he would have to communicate to the Israelites information about leaving times and marching pace that they otherwise would not know. If he is going to perform interventions of that nature, he might as well just perform a physical miracle without natural causes; it would accomplish the same end. There is no economy of explanation achieved by making the parting of the water wholly natural, because supernatural guidance by God is employed anyway.
Further, the Exodus story is full of miracles prior to the crossing. If those miracles were genuinely supernatural interventions, there would be no point in insisting that the Red Sea crossing was a wholly natural event. And if those miracles were not supernatural interventions, but themselves just natural events which were only “miracles of timing”, then the person holding that thesis needs to come up with a “natural” explanation for all the plagues, the rods and the serpents, etc. to parallel the “natural” explanation for the parting of the Red Sea. And even if that could be done, will the same person apply the same method to the New Testament? Will he try to explain water to wine, feeding five thousand, the resurrection of Lazarus, etc. as merely natural events which are miraculous only in their timing? Most of the Christians I know who are willing to entertain the “it was all natural” thesis for Old Testament miracles, balk at applying that to the New Testament ones. But is no good reason for such a distinction.
The whole thing smells of the most unhealthy kind of concordism, and I don’t see why anyone would be attracted to such explanations, either scientifically or theologically. They can be made to fit with modern scientific knowledge only by very complex and contrived arguments which most modern scientists (i.e, those who aren’t Christians of a Biblicist turn) are never going to accept anyway, and they solve no theological problem.