It sure is. There are 2 significant omissions/flaws in the reasoning behind Spork 21 IMO:

1. expressing and targeting ROI in Dash instead of USD (irrelevant to an investor)
2. modelling miners and masternodes as demographic groups instead of compoundable factors in the reward function (makes the analysis almost sociological in nature instead of economic)

So, to correct for these two errors we see that a completely different picture emerges as to the optimal approach.

Masternode ROI now becomes: (Reward + Capital Gain/Loss) / Collateral
Mining ROI now becomes: (Reward[at mining difficulty] + Reward[at zero difficulty])/Mining Cost

This is the more complete and correct description of the Dash business model which is the one that should have been used to determine an optimal "store of value" model IMO since roughly half of Dash's supply is effectively mined at zero difficulty. Any "miner" can therefore avail themselves of primary supply:

 • exclusively at mining difficulty
 • exclusively at zero difficulty or
 • a combination of both

Note that there are two significant implications of this which turn the reasoning behind Spork 21 on its head:

   1. while the Dash protocol can set the reward ratio in Dash, the market sets the reward ratio in Dollars

   2. following from 1, the Dash-determined reward ratio is IRRELEVANT unless its "tuned" to a market-competitive level

   3. the argument that "restricting supply to miners" is moot because in the holistic model, the entire supply is mined, just at distinct difficulty levels. It is also rendered moot because of the false assumption that demographics are coupled to reward categories which they clearly don't have to be

   4. the argument over whether or not miners run masternodes to subsidise mining is also moot because the Dash protocol ENCOURAGES IT, since the more masternodes a mining cartel runs, then lower their average mining difficulty level is. Masternodes are also a capital asset that can be cashed in at the end of use (unlike mining rigs) so the incentive for hybrid mining is substantial

***************** HOW TO FIX *****************

The problem is that mining profitability is set DIRECTLY by the free market (through difficulty adjustments) whereas masternode profitability (in USD) is set INDIRECTLY by the free market (with recourse to the coin price). The obvious answer therefore is to set the masternode margin at a profitability level where competitively is optimal. Since masternodes are effectively miners in the sense that they receive the primary supply, the logical free-market reference for their optimal profitability is a reasonably commercial mining profitability, say 10% or something. Anything else is going to cause the coin price to always be sub-optimal and if it's REALLY WRONG, it will cause it to bump along rock-bottom levels compered with fully mined coins.