User blog comment:B214/Question and Answers 6/@comment-185.112.105.215-20170106035554/@comment-29963364-20170107041009

I'm not calling Issei's IMT and CCP "irregular" because it's my personal theory. I'm calling them "irregular" because VALI HIMSELF SAID THEY WERE!!!

And when I said "a common trait of the Longinus is that they have more than one type of ability/power, while standard SG's usually have only one type." Here's a few examples:

 Boosted Gear 


 * Boost


 * Transfer


 * Other abilities that Ddraig had when he was alive.

 Divine Dividing 


 * Divide


 * Half Dimension


 * Other abilities that Albion had when he was alive.

 Regulus Namea 


 * Destructive force that can create craters.


 * Protection from projectiles.

 True Longinus 


 * Holy Aura/power


 * Change Fate/Destiny


 * It's Sub-Species BB literally has 7 different abilities (although they were created by Cao Cao)

 Dimension Lost 


 * Use mist to block attacks.


 * Use mist to teleport/transport people and objects.


 * Create artificial spaces/dimensions.

See the trend? Longinus SG's have more than one type of abilities. They don't have "the power to fuse abilities," They just naturally have different types of abilities.

So Issei using his Evil Pieces in conjuction with his Boosted Gear is completely unexpected, even though it's a Longinus. And look at Saji's Vritra SG's. They aren't Longinus, and yet they "fused" to create his BB.

The Irregular BB's we've seen have something in common: They were caused/created by altering them with something different from that SG.

 Yuuto Kiba 


 * Kiba used Light Attribute from his dead friends to alter his SG, Sword Birth.

 Genshirou Saji 


 * Saji achieved his BB by fusing his original SG, Absorbtion Line, with 3 other SG's.

 Issei Hyoudou 


 * Issei achieved his IMT & CCP by altering his original BB with his Evil Pieces.

Let's compare these cases with Tobio Ikuse...

Tobio achieved his Abyss-Side BB by focusing purely on his SG, relying only on his natural abilities. While Yuuto, Saji, and Issei achieved their BB's by using objects other than their original SG. They achieved BB in "irregular" ways, and achieved "irregular" BB's as a result.