Hindsight, and this particular situation, definitely makes this thought biased. But the idea remains... if you want a 50k position, and the price seems right, you can either dump it all in, or DCA it in with five 10k purchase over 5 weeks, or ten 5k purchases over 10 weeks (or whatever time/schedule you want). The reasons for DCA'ing it in are to spread your entry over time so that you average out your entry, and reduce the risk of buying right before a drop.
The idea behind my post isn't really intended to be one of trying to time the market (although I see that it practically is that), its one of assessing the reasons for doing the DCA in the first place (risk reduction) in the light of the current situation and your valuation of the company. It may not be optimal to dump it all in once, but when the risk/reward ratio is heavily skewed in your favour (which I think is still true at 60c, but was 'unbelievable value' at 40c) then you may want to adjust your DCA strategy to take that into account. It might be better to do larger purchases, more frequently. It might be better to break from your strategy to make an off-schedule purchase because things are looking fantastic.
Its true you can still get it wrong, and it may still go down. That is up to you and your own valuation of the company to decide how you want to play it. The potential downside at 60c is a lot less than the upside. The downside at 40c is tiny compared to the upside. I think our entry strategies need to take that into account.
In saying that, over the very long term perspective, you are correct that 40c or 60c may not really matter :)