This answer gives a great example of time-weighted return. It is essentially the cumulative return of each distinct portfolio period, ignoring the effects of large inflows or outflows.
Another method is money-weighted return, which is essentially IRR. Some examples of that are here and here. Money-weighted return takes into account when you invested. So if ...
A breakout is when prices pass through and stay through an area of support or resistance
In this case the analyst is predicting that Tesla will "break out" of the pattern and continue to trade (price-wise) above the previous level of resistance.
What technical factors cause the stock to breakout?
Nothing causes a breakout. It's ...