Isn't basing the multiplier on valuations at the latest investment round disingenuous? After all, its just a number the owners and investors hope someone will eventually pay for the company. It's the asking price set by people hoping for large returns.
Well it's a number that some people (the investors in that round) DID pay for a chunk of the company. If those investors have any sway on the board then it's well below the asking price for the entire company.
A valuation based on an investment round is the valuation of the complete company, not just the amount invested. So if I invest $1M for 10% of a company, that "values" the company at $10M.
