Elon Musk keeps spending money borrowed against Tesla shares to ... buy more Tesla shares.

Mark J. Terrill / Associated Press

Musk has bought about $35 million worth of Tesla stock in the past two months. In May, shares were sliding when he bought. Last week, when he laid of $25 million to purchase 72,000 shares, they had been rallying.

Musk isn't really getting paid by any of his companies (Tesla and SpaceX), so he funds his life by borrowing against his Tesla stake. He holds about 20% of the company and is its largest shareholder.

Last year, Tesla disclosed that Musk has loans with Morgan Stanley to the tune of about $624 million, pledged to Tesla stock as collateral. Presumably, this is the funding channel he's using to buy more stock.

I've never been comfortable with this arrangement. Musk has an incentive to move the stock price higher, although he has at times talked it down. With cash borrowed against Tesla's valuable shares, he buys more shares and ... the shares become more valuable! In a sense, this is pretend money creating speculative value.

Bulls see it as a positive because the CEO is putting his money where his mouth is. But it leaves Musk vulnerably to a stock decline that would undermine the value of his collateral, and it saves him from having to sell any stock to support his lifestyle.

It's difficult to be moralistic about this kind of stuff: Musk can spend his millions as he sees fit, and as far as I know, he isn't buying private islands. One could argue that he's all-in with Tesla. But one reason he is able to borrow so heavily is that Tesla is worth $50 billion — and yet in the year since the Model 3 launched, with 400,000 in pre-orders at $1,000 a pop, the company has barely made a dent in the order book.

Tesla doesn't need a higher stock price, and Musk himself doesn't need more shares, to rectify this problem. The company simply needs to jettison some of its more grandiose concepts about reinventing carmaking and just — make some cars! Musk might be in personal production hell, as he likes to call it, but the ability to lay your hands on $25 million whenever you need to should take the edge off.

The question is whether dropping that kind of coin right after you've handed out 3,000 pink sips sends the right message.