I do not support due to high potential for various perverse incentives and unintended consequences.

The most natural and robust interpretation of fees is an incentive for block-creators to include truncations in a block (payment for scarce block size). There are better mechanisms to in turn control block size and limit spam, such as a reward penalty. These will naturally pull fees higher via a market mechanism. Trying to go the other direction is akin to pushing on a rope. Reward penalties are especially suitable for CLAM since the block reward is fixed, unlike Bitcoin.

@dooglas you can (and will) still have a fee market if any portion of the fee, even 1%, is kept by the block creator. It will dramatically drive up the price of block space though, probably to levels above the social optimum. Though you still face the issue of hidden fees being paid out of band, and the incentive to do so will be large.

Again, none of this is likely what is intended. Tx fees are a round peg trying to be shoved into a square hole here.