Planned investigations

Seems that all 'improvements' I had in mind actually made its performance worse. Maybe I can better join the 'WorstBot' competition. Last chance is with 0.9d and if that one does not succeed, I will go sit in the corner and cry.

I would also suggest, to relabel old variant and put it in rumble. I feel that old rumble stats had a lot of disabled bots. It might appear that old version is better but it is actually not. Plus we have at least 3 new above top 100 bots which might pull your APS down.

That is true, it is also my intention to do so. I always compare against the older version via Botdetails, it let you see the differences betweeen the common pairings, so that really is the difference, even if only 1000 bots are in common. Just remove the 'd' from versionnumber and press Compare.

My main worry here is about difference in liteclient performance. Most of the old rankings were done with ancient version of robocode. It is possible that your old bot was tuned to exploit a glitch without you even knowing about.

I do know that some bots don't work very well in Robocode 1.9.2.x and/or Java 8. See f.e. Xiongan.xiongan and tcf.Drifter, they get scores of 0 against GrubbmThree, while on my system (1.9.2.5 and Java 7) they just work ok.

There is else but Java 7 vs 8. I ran tcf.Drifter vs. GrubbmThree 0.9d in robocode GUI with Java 8. Drifter constantly wins the match.

So I cannot attribute 100% loss which we see in rumble just to the Java version.

I did read somewhere that tcf.Drifter had some problem with the 1.9.2.5_beta versions, maybe someone is running the rumble with a non-official 1.9.2.5 version ?

Really something to try out, although I fear that then it has not enough speed to catch up on the other bot. First I test a re-entry of the original to determine the 'APS-rot'.