I think he's done great work, all things considered but...one's man's great is another's garbage,
If he hasn't written anything to your liking since his X-Men book started what makes you think he will write your one favourite character (whom he's not written at all) any better in a four issue LS?
It's the same with Excalibur's detractors...and Marauders...and X-Force (just about any X-book that many myself included have issues with)...If you didn't like the book/writer at issue one, and still hated the book/writer at issue ten and issue fifteen, what makes you think you will suddenly like the book/writer at the end of the run?