Did some testing for my own information. At 30%, when using 3 materials it's on average 0 gain. (3 reuses will coincide with about 1 failure trying to game it.)

At two materials, it's questionable. You're looking at a 1.5 successes per failure. Effectively 33% increased resource stocks by trying to game it.

At one material, you're looking at an average of 3 successes per 1 failure, which increases your effective resource stocks by 75% if you try and game it.

That said, you must still use resources, and I think the overall drop in glamour price has more to do with the materials being moved subsequently to yellow scrip vendors. Summer Indigo is still going strong.