It might be a bit too op in pvp so maybe make the glyph/talent that it doesn't snare.
Make glyph to channel mind flay while moving
Rather have a glyph of old school mind flay.
On topic: we are not going to get the ability to cast MF on the move in MoP. It just won't happen. The tl;dnr explanation is: spec identity, need, general caster movement dps and encounter design.
Taedas, you're right, but SW:P is awful to cast on the go if you just put up a trinket proc SW:P.
Please report any Code of Conduct violations, including:
Threats of violence. We take these seriously and will alert the proper authorities.
Posts containing personal information about other players. This includes physical addresses, e-mail addresses, phone numbers, and inappropriate photos and/or videos.
Harassing or discriminatory language. This will not be tolerated.