Tips for Mainlining and is this right approach ?

Removing the lower nodes and focusing on developing two main branches is a valid approach in main-lining. By doing so, you encourage the plant to direct more energy into developing the main colas, potentially increasing yields and promoting a more even canopy. Here are a few tips and considerations for your main-lining approach: Patience is Key: Main-lining can slow down the initial growth of the plant as it redirects energy to develop the main colas. Be patient, as the benefits usually become more apparent during the flowering stage. Maintain Symmetry: As you progress, try to maintain symmetry in the plant structure. This will help ensure even light distribution and promote balanced growth. Stress Management: Be mindful of the stress you're causing to the plant. While some stress can be beneficial for growth, excessive stress can lead to stunted development. Ensure that your pruning is done cleanly, and avoid causing unnecessary damage to the plant. Training Techniques: Consider using low-stress training (LST) techniques in conjunction with main-lining. This can involve tying down branches to encourage a more horizontal growth pattern and improve light penetration. Nutrient Management: Adjust your nutrient regimen to support the changes in the plant's growth pattern. As you remove certain parts of the plant, nutrient requirements may change. Regular Inspection: Regularly inspect your plant for any signs of stress, nutrient deficiencies, or pests. Catching and addressing issues early can prevent more significant problems later on. Remember that each plant is unique, and factors such as strain, environmental conditions, and individual plant health can influence the success of your main-lining technique. Adapt your approach based on how your plant responds, and don't be afraid to make adjustments as needed.

For a simple toping, it's very good. However, for mainlining, you should only keep one node. The principle was to sub-divide the main stem several times. If you keep several nodes, the ones underneath will be weaker. By the way, if you let your plant grow enough before toping, you can have a nice viable cutting. ^^