I asked a well-known military expert in the US to provide me with his evaluation of the battle in Nahr Al-Barid. He sent me this (he does not want to be identified):
"I would, really, but I do not have enough information. What we know is this: the ratio of soldiers killed to irregulars is extremely high (usually, 3-5 irregulars die for every regular army soldier). The numbers of Fath soldiers killed are dubious, the lebanese are including many civilians among them, fath acknowledged 5 dead in the last two days, vs over a dozen soldiers, and more than 30 injured. Fath seemingly does not have Anti-Tank weapons, yet, the army is not using its armored advantage to make any real gains. Fath also has no artillery. We know nothing about the clashes, but my feeling is this: the Army is barricading itself to protect its soldiers and using artillery from afar (for media effect, you cannot hit much in such a crowded camp, it is very easy to hide in buildings where artillery shells cannot be lobbed).

They make limited incursions and at a very high cost, probably through the wider streets, using armor and artillery cover. Will they actually control those 300 meters of advance? we do not know, my feeling is that they did not secure a safe area around their advance, but simply drove through a street, which could make them an easy target. Keep in mind, we are talking about very few irregulars facing several brigades. Also, so far, the only cases of serious Fath casualties are when Fath fighters get cornered inside a building (as in the second day of battles), they end up fighting to the death, taking several LA soldiers with them....Also, the fact that Fath "counter-attacked" yesterday means that they arenot on the defensive and there is no serious army push..."