Random thoughts regarding OPs question: -If ETF contains companies that pay dividends, and is a short ETF, you get hit when those those companies pay dividends, where as longs do not. -Most leveraged ETFs use some form of options/swaps in order to provide leverage - volitility in general has gotten crushed since 2009, but besides that, downside volitility is more expensive to protect against than upside in my experience - just do to the physics of the moves of underlying assets. So if volitility is getting crushed, and downside costs more than upside, chances are the leakage coming out of the short ETF will be greater than that coming out of long ETF. Just my two cents.
The OP was about commodity ETFs, so no dividends, but...If a stock goes ex-dividend the price of the stock falls by the amount of the dividend. So if you're short the stock, you have to pay out the dividend but get the get the gain from the drop so it nets out to zero. So a short fund won't be hit by dividends any more than a long one. Swaps aren't impacted by volatility, neither are commodities futures which are what are used for the commodity funds. It's all in the daily return feature of leveraged funds. It's a simple answer, do a little work to map it out on an excel spreadsheet and it will be obvious to you. No need to come up with all this other crap that's simply incorrect.
Did you read any of my posts? Have you read even a single prospectus on one of these funds? A 3X fund doesn't return 3 times the underlying. It returns 3 times the DAILY!!! return of the underlying. Let me give you a simplified example, you have commodity A and 3X fund B. You buy 1 "share" of each for $100. Commodity A starts at 100 and moves to 150 on day 1. That is a 50% increase, so your 3X fund increases by 3*50=150%. So your commodity is now at $150 and your 3X fund is now at $250. The next day, the commodity goes down 50 points. Your Commodity A is now at $100. The 50 point move = 50/150= .33% decrease. Since the 3X fund returns the percentage daily return of the underlying, it moves down 3*33%=99%. Since 99% of 250 is $247.50, your 3X fund is now worth $2.50. If you naively didn't understand this concept, you'd expect your 3X fund to be at $100 since the commodity price was the same at the end of day 2 as at the beginning of day 1. And you'd have lost $97.50 of the $100 you invested in the 3X fund. Perhaps you may even be thinking, "Maybe I should have paid attention to that Sig fellow, or at least read the prospectus"? Obviously most commodities don't move 50% or 33% in a day, I used those numbers to make the point blindingly obvious. However the math is the same for a 5% move up followed by an equal dollar move down on the underlying, and as that difference between the daily returns of the 3X fund and the total returns of the underlying add up you get wildly different results from what you'd expect. In the end, the returns of the 3X fund end up having little to nothing to do with the underlying and almost everything to do with the path the underlying took. Over time can get you way more that 3X the return or way less, it all depends on the path the underlying takes.
If prices are rising or look like they will, on a 3X bull ETF, buy it. If prices are rising or look like they will, on a 3X bear ETF, buy it. --It's as simple as that. --Just like any other instrument you trade, you depend on trend for profit--Period.
If you don't get this concept, and you clearly don't, then it's not possible for you to ever understand the answer to your question. This is like someone asking why their put option went to zero but refusing to listen when someone explains to them how a put option works.
%% Speaking of price rise X 3......that sure is a weak uptrend on SPXL, UPRO,TQQQ, SPY, QQQ, ES...; not a prediction, some maybe front running a sell in May -hey. I like good uptrend$ but that is not a good one, it may go up some more.................................................................