This comes just a day after Deni challenged him to a debate. For the stability of Somalia, this cannot be seen as a wise move, as it further strains relations between the FGS and the Federal Member States. Having mostly subdued Laftagareen, perhaps he feels comfortable enough to make this decision.
From a political strategy standpoint, this is a high-risk, high-reward move. In one stroke, he’s allied with and legitimized a force in Puntland, posing a threat to the region’s stability.
One major issue is that many people have convinced themselves that HSM is foolish, which couldn't be further from the truth. He is one of the few Somali politicians with a legitimate PhD from a Western university. While he is incredibly corrupt and a notorious flip-flopper, he is far from dumb. Every action he takes is aimed at consolidating more power. If you focus on that thread, his moves appear quite consistent. In the tug-of-war between the FGS and FMS, the FGS seems to be gradually gaining the upper hand.
I've generally been positive about Deni's tenure, but it's time to take off the rose-colored glasses. How he's allowed both ISIS in the mountains and the PSF to remain persistent threats is beyond me.