tbh, transports are still, even after the proposed changes way overpowered (short of "blow up if out of supply after 10 seconds (so that you can still bypass a defended wormhole but not much more than that!), i mean, i can see why people want to have them... they are literally the ultimate deep raid utility.
I only even bothered to try this because i was bored, and i am on my last branch to the last homeworld, pack up 3 fake transports, move them to the front of the formation, pack up your real formation, and pack up 3 fake transports at the end. give move order to your target planet and sit back. Its the ultimate deep raid convoy of death. If you take time to optimize position (bit space between fake ones) you will lose nothing.
I lost 0 transports anyhow, reached the planet i wanted which was not on alert and had only 500 ships on it (turrets and ships), it was cleansed within seconds. Then i followed my entire trail back, destroying the home stations and cutting planets off from supply in a huge chain, from this point on i had 6 ai planets cut from supply, and could fly through them at my leisure - the freed ships all trickled against my superior defenses. And i had a open path to the enemy homeworld minus its core defense worlds (it was a long branch ^^)
I am sorry, but this needs a big fat nerf. The ai does trail fake transports, thats true - but the ai also has to do it since deploying your fleet way out of range at the border means you can roll up entire planets from the backdoor or deploy WAY nastier things. Like 600 merc bombers and beeline to its command station.
There is only 1 working nerf for this, out of supply means you get 10 seconds where you can run as fast as you can at all full speed. After that its total engine failure without chance of repair.
Thats just my opinion though, i do not use transports because i think its sort of a cheat. ^^