Let's use your example breakdown but a price of $1 a share and 100,000 shares.
FFX - $35,000 (35%) LLL - $65,000 (65%)
But you only get 1 LLL for each 1.4 FFX, so you will now have 71,428 shares of LLL and 100,000 shares of FFX.
So each FFX share now has a cost base of 35c instead of $1 - easy.
Do the LLL shares have: a) A cost base of 65c per share (or "each LLL share will have a cost base of 65% of your average cost base for your FFX shares") b) A total cost base for all shares of $65,000 = 91c a share cost base (or "your total LLL shares will have a total cost base equivalent to 65% of your total cost base for your FFX shares")
Presumably it has to be (b)?
At that point I'm not sure the split really matters as such in the long-term from a tax payable perspective (will affect timings and potentially what is a loss vs gain on paper, but should in theory net out?) but it may have the potential psychologically to drive buy/sell behaviour for a period of time.
Addendum to the above: a lot of people are presumably going to have the wrong cost base showing up on their broker tool for a time. Will that potentially affect psychology of trades too?
