High yield investing
High yield investing is best thought of as dividend growth investing without the growth. The lack of growth is compensated for with a higher yield which is then reinvested "manually" back into the portfolio. It is not meant as a short cut or an excuse to accumulate fewer assets.
A typical high yield portfolio will pay 6-10% per year. Out of those, 3% (or whatever the safe withdrawal rate is) can be spent while the rest must be invested back into the portfolio in order to increase the amount of otherwise non-growing dividends to keep up with inflation.
Portfolios are built manually using fundamental stock analysis (FSA). FSA can be learned from scratch by someone who masters basic math (e.g. 7*(-8)/4+3=-11). Expect needing 300-1000 hours of study using a curriculum of first and second year business books.
Advantages
The benefit is that it removes the risk of principal loss if growth targets aren't met as these are typically priced into the share price as premium for a dividend growth stock.
High-yield means a shorter duration because more cash is returned in the front months. This means that high-yield portfolios are less vulnerable to changes in future growth rates.
Disadvantages
The main disadvantage (which can also be seen as the main advantage) is that the share price is almost exclusively a function of the dividend. This means that if the dividend is changed for any reason, the share will respond immediately. However, unlike dividend growth companies, changes in earnings or revenue will usually not impact the share price dramatically.
The downside is that such companies are typically in declining industries such as tobacco, land line telecom, postal services, etc.