This contrasts with the defensive so-called normal or standard Fourth File Rook that keeps the bishop diagonal closed until the player is ready for a counterattack so that they may avoid rough and tumble battles initiated by their opponent.
For this reason ranging rook will attempt to block the bishop's diagonal early, and will enter battle as soon as the king is castled.
Furthermore, even if Bear-in-the-hole is built up, since it makes the silver and golds to lean heavily on one side it becomes really easy for ranging rook to find good places to drop the bishop in hand, and even against the solidness of a Mino castle it becomes easy to wage battle, hence the ranging rook is at advantage.
Moreover, since White's R-42 places the rook temporarily in the fourth file, it becomes a preparation for a powerful counterattack against Black's B*6e.
An opening to build Bear-in-the-hole from Bishop Exchange Fourth File Rook has also been created, the so called Leghorn Special (白色レグホン・スペシャル hakushoku reguhon supesharu or, most commonly, the abbreviation レグスペ regusupe).
In addition, according to Ueno, Takeshi Fujii had been exploring novel countermeasures against Anaguma to replace the Fujii System when this opening made its appearance in the world of professional shogi after being popular among college players, and his adoption of the opening caught a lot of attention and produced a craze for the strategy in the subsequent years.
White may opt for an immediate exchange of the eighth-file pawns, but this is a blunder, as Black can place a bishop on 77, forking the rook on 86 and the silver on 22.