In an article discussing the viability of Jerusalem being a capital city in the days of David and Solomon (a strongly debated issue of historicity of the two kings currently enfolds in the July/August 1997 issue of Biblical Archaeology Review), the following information is supplied with this photograph:
"Inscribed potsherds (ostraca) from the eighth and seventh centuries B.C.E. (Before Common Era, or B.C.), found in both Israel and Judah, provide evidence for writing in the tenth century B.C.E. "These ostraca contain Hebrew characters as well as signs and numerals in hieratics-a cursive form of Egyptian hieroglyphics.
"Curiously, these hieratic signs do not appear in contemporaneous documents of Israel's neighbors, even though Egypt's relations with Philistia and Phoenicia in the ninth and tenth centuries B.C.E. were much closer than those with Israel.
"Moreover, no eighth- or seventh-century Egyptian parallels have been found for many of the signs on the Hebrew ostraca." (Cow Town or Royal Capitol? Evidence For Iron Age Jerusalem, Nadav Na'aman, Biblical Archaeological Review, July/August 1997, p. 45).
Here we have various Israelite potsherds, like the one pictured, with a hieratic Egyptian script. Some of the signs aren't even found in Egyptian ruins, signifying the probability that Israel had adapted hieratic Egyptian to its own use. That this use of Egyptian hieratic was ONLY used by Israel, and not by its neighbors is highly significant. The Book of Mormon's claim of "Reformed Egyptian" would be invalidated had the Nephites claimed lineage from the Philistines or Phoenicians.
Being that this use of hieratic Egyptian was evident in the 7th-8th centuries B.C.E., it is very possible that such training was passed down to Lehi and Nephi, and finding its way into Nephi's plates.