Yes, the short term EMA on weekly are working, though there are a few periods since IPO that they were uncertain. Recently they're been very reliable.
The volatility in RV's SP these past few years has proven the EMA crossovers to be effective, but who would've expected any of the RV's SP to be so volatile?
Even very conservative TA, the 50/200EMA crossover (daily SP chart) has worked since IPO. This chart doesn't even show the SP, it's just shows the crossovers, green is a buy, red is a sell.
It's not about predicting the future, trading the market is about responding to the 'now' with some assumptions about probability. It assumes one can absorb the trading fees, and potential to be taxed as a trader, and still be profitable, with something else better to do with their capital while they're waiting for the next buy signal, which the chart does not help with.
Disc: not trading OCA, but you can easily see that even the most conservative TA would have been effective and no trader would be holding or buying OCA at the current point in time. They'll be looking for the entry/re-entry, which is possibly why a few traders are so prominent on this thread recently.