Dear Kollel,
(a) In item 4a it states that carrying 4 amos within the area is permitted. This is not meaningful, sine the area is less than 4X4 tefahim!
(b) Items 2 and 3a: the width is NOT "4X4 tefachim", but GREATER OR EQUAL to 4X4 tefahim: if only 4X4 again carrying 4 amos is not possible.
Shana Tova,
Yeshayahu HaKohen Hollander
(a) First of all, although it is not possible to carry four Amos inside of the Reshus, it is possible to perform a Hanachah inside the Reshus after carrying four Amos in Reshus ha'Rabim. (This is included in the category of "Carrying (i.e. Akirah and/or Hanachah) four Amos within the area.") One would be exempt for such a Hanachah.
But more to the point, if the Reshus is 10 Amos by 3.9 Tefachim it is still considered to be less than 4x4 Tefachim and it is a Makom Petur. One is permitted to carry in such a Reshus more than 4 Amos.
(b) You are quite correct. I thought it was evident that any area more than 4x4 Tefachim had in it 4x4 Tefachim and was included in that category of Karmelis, but we could make it more explicit. In which case, I suppose that we should also empahsize in 2A that the height of Mechitzos of Reshus ha'Yachid should be 10 Tefachim or more .
Thank you, Yeshayahu - keep up your terrific work!
Mordecai Kornfeld