So I have seen this said by a few people around the forums, and find myself also effected by it. Due to getting insulted by pulling my 5th +1 stat tome in 'Legendary' content (1 from tempest LE, 3 from Shroud LH/LE, and 1 from Hound LH) I wanted to put the knowledge out to people as direct as I could, at least on this venue of communication.
Simple fact being: Tomes drop rate patched in U29 caused all tomes to drop only +1 values.
Reported now 4 times, and figured to put up here, in it's own thread, to receive comment from moderators. That is all.