Why is it listed as +99???

lishogi.org/analysis/+R+R+R+R+R+R+R+R+R/PPPPPPPPP/lnsgkgsnl/1r5b1/ppppppppp/9/PPPPPPPPP/1B5R1/LNSGKGSNL_b_-_1

It should be like +3.7, for example.
The pawns are useless!

Engines aren't perfect. While its obvious to a human who looks at the position that the all the rooks on the first rank are trapped there and won't impact the game, the engine doesn't know that. All the engine sees is a board where one player has an overwhelming material advantage and the other player does not have any sort of positional advantage to balance that out.

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I'm guessing the engine evaluation doesn't handle positions which have double the number of normal pieces. Actually here it looks difficult for sente to promote more pieces and easy for gote to promote, so I would expect a negative evaluation.

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