I'm also quite curious about this. If it's a static rate (like I'm hoping), I'll just wait for my multiplier to run down, and then use all my charms at a constant 10% increase. If it's not, training summ is effectively a giant waste of time. The latter doesn't make much sense, but knowing jagex... "Following feedback from Marchs Bonus XP Weekend, the boost to Summoning XP will be limited to 10% over the course of the four days." I'm pretty sure this means that it will be 10% the entire weekend. Although, Jagex is known for writing things in a vague manner.. I agree with that. I think it's because players were annoyed when they had used millions on summoning to later find out they could save half the money by waiting for the XP weekend. But still, it's a rare chance to get some more xp, and they barely boost summoning with anything at all. They should really set summoning to 150% too!