You're right only a persons discretional income should be invested in Bitcoin and not the other way round , investing an entire life savings in Bitcoin all at once is financial recklessness which could also lead to financial discomforts. When a person invest his entire savings in Bitcoin,at that point he's now financially vulnerable because he's empty without any funds to sort out his Bills and other of his necessary needs. Since he is a long term investor,there is no points pouring all of his funds at once in Bitcoin of which is very wrong from the starts. A smart thinking investor would only invest in Bitcoin appropriately without overdoing it or stepping out of his financial limits.
I agree with you, one of the most important things in Bitcoin investment is to invest with financial balance, if you invest aggressively, an investor will panic very easily, because when the market is down, that person will not only suffer from mental stress, but he may also make any wrong decision due to excessive panic. But if he continuously invests in Bitcoin through DCA, he will never panic during volatility, because he is increasing his Bitcoin holding at an average price through continuous purchases, so volatility will never scare him too much. So, before investing, you need to know about these volatility issues, and instead of deciding to invest aggressively, deposit Bitcoin in DCA through prudent income, and keep emergency funds ready to protect the investment in the long term.
If to invest aggressively will make you panic when there's a dip, it means that you shouldn't invest aggressively but use the amount of money from your discretionary income that will keep your mind at rest if there's a dip or not for your weekly DCA . It's better to use small amount to buy gradually every week 4-10 years and above and be consistent with it than buying with an amount that will make you panic and sell before your desired time.
Buying aggressively is good when you have the money to do so, because it will help you increase your bitcoin portfolio in a fast pace but let it be within your discretionary income, if you invest buy aggressively with money that's beyond your discretionary income, you are gambling and will sell your bitcoin at loss, especially when the price of bitcoin is below your entry point.
I mean the basic purpose of investment is to get something going (interest) and one mustn't force their way especially when you feel the market is at advantage to you and you think you desperately need to buy big since the price is in favour because of maybe a dip in price, but doing that will just give you restlessness since it's out of discretionary income and anything that's out of your comfort zone in terms of investment is actually a really bad idea and going slow and steady would be the best option just as advice but the issue with most persons is that they lack to have patience and control which can make due to decision making results.